Amazon Web Services SAA-C03 AWS Certified Solutions Architect - Associate (SAA-C03) Exam Practice Test

AmazonTextractcan extract text from the PDFs, andAmazon Comprehendis the most suitable service to analyze the extracted text for sentiment and insights. Comprehend offers a fully managed, low-operational overhead solution for analyzing text data. The results can then be stored in anAmazon S3bucket, ensuring scalability and easy access.

Option A: Athena is for querying structured data and is not suitable for sentiment analysis.

Option B: SageMaker adds complexity and is not necessary when Comprehend can handle sentiment analysis natively.

Option D: QuickSight is used for visualization and analytics, but it does not provide sentiment analysis.

AWS References:

Amazon Comprehend

Amazon Textract

Predictive scaling in EC2 Auto Scaling uses machine learning to analyze historical load and forecast future capacity needs, then pre-scales capacity before the demand occurs. It is specifically designed for recurring, cyclical workloads such as weekly batch jobs.

In this scenario:

The workload pattern is known and recurring (weekly scripted jobs).

The company explicitly does not want to manually analyze trends.

They need capacity to be ready 30 minutes before jobs start.

Predictive scaling lets you:

Set the metric (CPU utilization) and target (60%).

Configure the policy to pre-launch instances 30 minutes in advance, satisfying the requirement automatically with minimal operational overhead.

Dynamic scaling (Option A) reacts after CPU increases, not before.

Scheduled scaling (Option B) requires manual analysis and ongoing adjustment of capacity values.

EventBridge + Lambda (Option D) introduces unnecessary custom logic and still reacts after CPU reaches 60%, not 30 minutes before.

With AWS Shield Advanced, you can add multiple protected resources (like ALBs) to a protection group and choose an aggregation type for mitigation and billing.

Sum aggregation provides combined protection for all resources in the group during blue/green deployment.

“You can add multiple resources to a Shield Advanced protection group and choose an aggregation type. Sum aggregation provides combined protection across all resources.”

— Shield Advanced Protection Groups

This ensures the new ALB inherits protection and avoids additional configuration during deployment.

Amazon Neptune: Neptune is a fully managed graph database service that is optimized for storing and querying highly connected data. It supports both property graph and RDF graph models, making it suitable for applications that need to analyze relationships between data entities.

Neptune Streams: Neptune Streams captures changes to the graph and streams these changes to other AWS services. This is useful for applications that need to monitor and respond to changes in real-time, such as providing recommendations based on user interactions and relationships.

Least Operational Overhead: Using Neptune Streams directly with Amazon Neptune ensures that the solution is tightly integrated, reducing the need for additional components and minimizing operational overhead. This integration simplifies the architecture by eliminating the need for a separate service like Kinesis for change processing.

For logs that are:

Written and processed within a short period (24 hours)

Accessed quickly for compute/analytics

With unknown object count and size

Amazon S3 Standard is the most appropriate and cost-effective. Intelligent-Tiering is designed for data stored for longer periods (typically 30+ days) with changing access patterns and charges a per-object monitoring and automation fee that becomes inefficient for very short-lived objects.

S3 Glacier Deep Archive and S3 One Zone-IA are optimized for long-term archival or infrequently accessed data with retrieval time or availability constraints that are not suitable for nightly active processing.

The company is looking for a solution that provides single sign-on (SSO) across multiple AWS accounts while continuing to manage users and groups in their on-premises Active Directory (AD). AWS IAM Identity Center (formerly AWS SSO) is the recommended solution for this type of requirement.

AWS IAM Identity Centerprovides a centralized identity management solution, enabling single sign-on across multiple AWS accounts and other cloud applications. It can integrate with on-premises Active Directory to leverage existing users and groups.

By configuring a two-way forest trust relationship between AWS Directory Service for Microsoft Active Directory and the company's on-premises Active Directory, users can be authenticated by their on-premises AD and still access AWS resources through IAM Identity Center. This solution allows centralized management of AWS accounts within AWS Organizations.

The two-way trust allows mutual access between the on-premises AD and the AWS Directory Service. This means that users and groups in the on-premises AD can be used for authentication in AWS IAM Identity Center while maintaining the existing identity management system.

AWS References:

AWS IAM Identity Center Documentation

AWS Directory Service for Microsoft Active Directory Trust Relationships

AWS Directory Service Integration with IAM Identity Center

Why the other options are incorrect:

A. Create an Enterprise Edition Active Directory in AWS Directory Service: This would require setting up a new directory and managing it in AWS, which adds unnecessary overhead. The requirement is to continue using the existing on-premises AD, making this option unsuitable.

C. Use AWS Directory Service and create a two-way trust relationship: While this approach establishes a trust between on-premises AD and AWS Directory Service, it does not address the single sign-on (SSO) requirements across multiple AWS accounts through IAM Identity Center.

D. Deploy an identity provider (IdP) on Amazon EC2: This is more complex than necessary and introduces more management overhead. AWS IAM Identity Center natively supports integration with on-premises Active Directory without requiring a custom IdP.

For latency-sensitive, global, non-cacheable workloads such as online gaming, AWS recommends AWS Global Accelerator. Global Accelerator:

Provides static anycast IP addresses at AWS edge locations worldwide.

Routes traffic over the AWS global network to the application’s ALB endpoint in the optimal Region, reducing latency and jitter versus internet-based routing.

Supports TCP and UDP and is ideal for real-time gaming traffic.

CloudFront (Option A) is optimized for caching HTTP/HTTPS content and does not significantly improve latency for highly dynamic, interactive gaming traffic.

API Gateway (Option B) is not needed in front of an ALB for this gaming pattern and introduces extra hops and cost.

Geolocation routing (Option D) with multiple Regions adds complexity (including data replication for DynamoDB) and still relies on DNS.

AWS Service Catalogallows organizations to centrally manage commonly deployed IT services and offers self-service deployment capabilities to customers. By creatingService Catalog products, the consulting company can package their solutions and tools for easy reuse by customers while maintaining central control over configuration and access. This provides a standardized and automated solution with the least operational overhead for managing and deploying solutions across different customers.

Option A (CloudFormation): CloudFormation templates are useful but don't provide the same level of management and user-friendly self-service capabilities as Service Catalog.

Option C (Systems Manager): Systems Manager is more focused on managing infrastructure and doesn't offer the same self-service capabilities.

Option D (AWS Config): AWS Config is used for tracking resource configurations, not for deploying solutions.

AWS References:

AWS Service Catalog

The design already uses one transit gateway (TGW) per Region and inter-Region TGW peering, which addresses the multi-Region AWS-side routing. The remaining requirement is to extend on-premises connectivity over Direct Connect so that on-premises networks can reach VPCs attached to the TGWs across all three Regions. The most operationally efficient and scalable approach is to use AWS Direct Connect Gateway (DXGW) with a transit virtual interface (transit VIF) and then associate the Regional transit gateways to that DXGW.

Option C is purpose-built for this: a transit VIF is specifically used to connect a Direct Connect connection to a Direct Connect gateway, and a DXGW can then be associated to multiple transit gateways (and can be used across Regions), enabling centralized connectivity from on-premises to TGW-connected VPCs. With TGW attachments and TGW route tables, you can propagate and control routes across many VPCs and accounts, which fits the “50 accounts, thousands of VPCs” scale. Inter-Region TGW peering then allows on-premises routes learned via the DXGW/TGW in one Region to reach workloads in the other Regions through the TGW peering relationships, subject to routing configuration.

Option A is too limited and not scalable because it ties Direct Connect to a virtual private gateway (VGW) associated with a single VPC, which does not meet the multi-VPC, multi-account hub-and-spoke requirement. Option B incorrectly suggests associating a DXGW with a VGW “in each VPC” (VGW is per VPC and would not scale well here, and it doesn’t integrate with the TGW hub design you’ve already built). Option D is not the intended pattern: Site-to-Site VPN and public VIF do not replace the DXGW + transit VIF architecture for large-scale TGW-based private routing.

This question focuses on scalability, operational overhead, and performance during unpredictable workloads.

API Gateway + AWS Lambda enables serverless compute, which scales automatically based on the number of requests. It requires no provisioning, maintenance, or patching of servers — eliminating operational overhead.

Amazon DynamoDB is a fully managed NoSQL database optimized for high-throughput workloads with single-digit millisecond latency.

Amazon S3 is designed for high availability and durability, and is ideal for storing unstructured content such as user-uploaded images.

By leveraging these fully managed and scalable services, the architecture meets the requirement of supporting rapid user growth while minimizing operational complexity. This solution aligns with the Performance Efficiency and Operational Excellence pillars in the AWS Well-Architected Framework.

???? References:

Serverless Web Application Architecture

Using DynamoDB with Lambda

Best Practices for API Gateway

Amazon FSx for Lustreis a high-performance, fully managed file system that is ideal for applications requiring low-latency access to shared storage, especially in use cases like gaming where high throughput and low latency are essential. It integrates easily with EC2 instances, providing fast and scalable shared storage, and supports custom protocols for specific application needs.

Option A (FSx File Gateway): FSx File Gateway is designed for hybrid cloud storage and is not suited for high-performance gaming workloads.

Option B (EC2 Windows instance): Setting up a file share on a Windows instance would introduce additional administrative overhead and would not provide the necessary performance.

Option C (EFS with Lustre): While Lustre is integrated with FSx, EFS does not natively support Lustre.

AWS References:

Amazon FSx for Lustre

For the migration of data from an on-premises Oracle database to Amazon Aurora PostgreSQL, this solution effectively handles schema conversion, data migration, and ongoing data replication.

AWS Schema Conversion Tool (SCT): SCT is used to convert the Oracle database schema to a format compatible with Aurora PostgreSQL. This tool automatically converts the database schema and code objects, like stored procedures, to the target database engine.

AWS Database Migration Service (DMS): DMS is employed to perform the data migration. It supports both full-load migrations (for initial data transfer) and continuous replication of ongoing changes (Change Data Capture, or CDC). This ensures that any updates to the Oracle database during the migration are captured and applied to the Aurora PostgreSQL database, minimizing downtime.

Why Not Other Options?:

Option A (SCT + DMS full-load only): This option does not capture ongoing changes, which is crucial for a live database migration to ensure data consistency.

Option B (DataSync + S3): AWS DataSync is more suited for file transfers rather than database migrations, and it doesn’t support ongoing change replication.

Option D (Snowball + S3): Snowball is typically used for large-scale data transfers that don’t require continuous synchronization, making it less suitable for this scenario where ongoing changes must be captured.

AWS References:

AWS Schema Conversion Tool- Guidance on using SCT for database schema conversions.

AWS Database Migration Service- Detailed documentation on using DMS for data migrations and ongoing replication.

Detailed Explanation:

A. ECS + API Gateway:Overly complex and costly for an on-demand, intermittent workload.

B. EventBridge + SNS:EventBridge schedules are unnecessary for on-demand generation.

C. EKS + API Gateway:Overkill for this use case, with high operational overhead.

D. Lambda + SES:Most cost-effective and efficient solution for generating and emailing reports on demand.

EBS Encryption:

Default EBS Encryption: Can be enabled for new EBS volumes.

Use of AWS KMS: Specify AWS KMS keys to handle encryption and decryption of data transparently.

Amazon RDS Encryption:

RDS Encryption: Encrypts the underlying storage for RDS instances using AWS KMS.

Configuration: Enable encryption when creating the RDS instance or modify an existing instance to enable encryption.

Least Amount of Changes:

Both EBS and RDS support seamless encryption with AWS KMS, requiring minimal changes to the existing infrastructure.

Enables compliance with regulatory requirements without modifying the application.

Operational Efficiency: Using AWS KMS for both EBS and RDS ensures a consistent, managed approach to encryption, simplifying key management and enhancing security.

AWS Global Accelerator improves the performance and availability of applications by directing user traffic through the AWS global network of edge locations using anycast IP addresses. It reduces latency and jitter for global users accessing applications in a single Region.

Why this works:

Global Accelerator routes user requests to the nearest AWS edge location using AWS’s high-performance backbone network.

It then forwards traffic to the optimal endpoint — in this case, the public API hosted on EC2.

This is much more cost-effective and requires less operational complexity than deploying and maintaining multiple API Gateway endpoints across regions (Option B), or setting up Direct Connect links for every international location (Option A).

Option C requires no application change and is designed specifically for latency improvement and high availability.

???? References:

AWS Global Accelerator Documentation

Use Cases for Global Accelerator

Performance Improvements for Global Users

S3 One Zone-IA:

Suitable for infrequently accessed data that doesn't require multiple Availability Zone resilience.

Cost-effective for storing user-uploaded images that are only used for AI model training twice a year.

S3 Standard:

Ideal for frequently accessed data with high durability and availability.

Store premium user-generated AI images here to ensure they are readily available for download at any time.

S3 Standard-IA:

Cost-effective storage for data that is accessed less frequently but still requires rapid retrieval.

Store non-premium user-generated AI images here, as these images are only downloaded once every 6 hours, making it a good balance between cost and accessibility.

Cost-Effectiveness: This solution optimizes storage costs by categorizing data based on access patterns and durability requirements, ensuring that each type of data is stored in the most cost-effective manner.

Amazon Elastic File System (EFS) is the ideal solution for migrating legacy applications that require NFS (Network File System) communication. EFS provides fully managed, scalable NFS storage in the cloud, and it supports the standard NFS protocols, allowing the legacy application to continue using NFS without modification after migration to AWS.

Key AWS features:

NFS Support: EFS natively supports the NFSv4 protocol, which makes it the best solution for workloads that rely on NFS communication.

Scalability and Availability: EFS automatically scales as application demands grow, making it a highly available and reliable storage solution.

AWS Documentation: According to AWS’s best practices for file storage, EFS is recommended for any workloads requiring NFS support in a cloud environment​​.

Explanation (AWS Docs):

DynamoDB Accelerator (DAX) is a fully managed, in-memory cache specifically for DynamoDB. It reduces read load and latency without requiring code changes (only SDK config). This is the least development effort.

“Amazon DynamoDB Accelerator (DAX) is a fully managed, highly available in-memory cache for DynamoDB that delivers microsecond read performance and requires minimal application changes.”

— Amazon DAX

Amazon CloudFront is a global content delivery network (CDN) that caches and distributes content to users with low latency. By setting the existing ALB as the origin, CloudFront can cache dynamic and static content closer to users worldwide, improving performance and reducing the load on the application servers. This is the most cost-optimized and AWS-recommended way to globally serve dynamic content for web applications.

Reference Extract:

"CloudFront accelerates delivery of both static and dynamic content, reducing latency and offloading origin resources by caching content at edge locations."

Source: AWS Certified Solutions Architect – Official Study Guide, CloudFront and Global Application section.

Explanation (AWS Docs):

DynamoDB has a built-in feature called Time to Live (TTL) which automatically deletes expired items without manual intervention. This requires adding a timestamp attribute and setting a TTL on the table. This is the lowest operational overhead approach.

“You can use DynamoDB TTL to automatically delete items after a specified time, reducing storage costs and administrative overhead.”

— DynamoDB TTL

Amazon EFS is a “fully managed, elastic, shared file system” that provides NFSv4 access across many EC2 instances and AZs, ideal for lift-and-shift of Linux NFS workloads. AWS DataSync “automates moving data between on-premises NFS servers and Amazon EFS,” performing incremental, parallel transfers with encryption and integrity checks, enabling cutover with minimal disruption. FSx for Lustre (A) targets HPC and S3-backed workloads, not general NFS shares. FSx for Windows (D) exposes SMB, not NFS. S3 (C) is object storage and not directly NFS-accessible by multiple EC2 hosts. EFS + DataSync satisfies NFS compatibility, multi-client access, and low-touch migration while remaining cost-effective for a 200-GB dataset.

Amazon S3 Intelligent-Tiering: This storage class is designed to optimize costs by automatically moving data between two access tiers (frequent and infrequent) when access patterns change. It provides cost savings without performance impact or operational overhead.

S3 Lifecycle Rules: By creating an S3 Lifecycle rule, the company can automatically transition objects to the Intelligent-Tiering storage class. This eliminates the need for manual intervention and ensures that objects are moved to the most cost-effective storage tier based on their access patterns.

Operational Efficiency: Intelligent-Tiering requires no additional management and delivers immediate availability for frequently accessed objects. This makes it the most operationally efficient solution for the given requirements.

To improve scalability and availability, EC2 Auto Scaling across multiple Availability Zones with an Application Load Balancer ensures resilient infrastructure. Migrating to Amazon Aurora MySQL with reader endpoints reduces read latency by offloading read traffic to replicas in otherAZs, while also increasing high availability.

Deploying the web application on EC2 instances in private subnets behind an internal ALB ensures that the application is not directly accessible from the internet. By setting up a Site-to-Site VPN connection, the application can be accessed securely from the company's office network. Deploying NAT gateways in public subnets allows instances in private subnets to initiate outbound connections to the internet for downloading security patches.

EBS Elastic Volumes allow you to dynamically increase storage size, adjust performance, and change volume types without downtime, supporting operational efficiency and scalability for SaaS applications that need to allocate varying storage amounts to customers.

Migrating from EBS to S3 (Option A) is not suitable since S3 is object storage, not block storage, and does not support block-level I/O required by many applications. EFS (Option B) and FSx (Option C) are shared file systems, which might add unnecessary complexity and cost, especially if the application depends on block storage semantics.

Using Lambda to automate Elastic Volumes resizing provides cost efficiency by allocating resources on demand and reduces operational overhead, aligning with AWS operational excellence and cost optimization best practices.

Amazon SQS FIFO queues guarantee the order of message delivery and ensure that each message is delivered exactly once. Paired with AWS Lambda, this creates a scalable, fault-tolerant architecture that processes each order in order and prevents duplicates, which is critical for ecommerce workflows.

Option A:The ALB must accept HTTPS traffic from the public internet. Allowing inbound traffic on port 443 from 0.0.0.0/0 enables this functionality.

Option C:The ALB must forward HTTPS traffic to the web application servers on port 443. Outbound traffic for port 443 must be allowed for this communication.

Option E:The ALB must perform health checks on the web application servers over HTTPS on port 8443. Outbound traffic for port 8443 must be allowed for this purpose.

Option B:Allowing all outbound traffic is overly permissive and does not align with the specific requirements.

Option D and F:Inbound traffic to the ALB from the web application instances is unnecessary because the flow of traffic is from the ALB to the web application instances, not vice versa.

AWS Documentation References:

Application Load Balancer Security Groups

Health Checks for ALBs

AWS Fargate with Amazon ECS is a serverless, fully managed compute engine for containers. Fargate eliminates the need to provision or manage servers, and is ideal for periodic, long-running batch jobs. You only pay for the resources consumed during job execution, making it cost-effective for jobs that run infrequently. Lambda is not suitable because the maximum execution time is 15 minutes, but the job can take up to 2 hours.

AWS Documentation Extract:

“AWS Fargate lets you run containers without managing servers or clusters. Fargate is ideal for batch jobs, event-driven processing, and scheduled tasks that require hours of compute.”

(Source: AWS Fargate documentation)

A: Reserved Instances are cost-inefficient for infrequent workloads and require server management.

B: Lambda has a hard limit of 15 minutes per execution, insufficient for this job.

D: ECS on EC2 requires you to manage and provision EC2 instances, increasing cost and management overhead.

Amazon EBS io2 Block Express volumes are designed to deliver sub-millisecond latency and up to 256,000 IOPS per volume, with durability and high availability. This makes io2 Block Express the recommended choice for workloads requiring very high and predictable IOPS, such as enterprise databases and high-transaction-rate applications.

Reference Extract:

"EBS io2 Block Express volumes deliver up to 256,000 IOPS and sub-millisecond latency, supporting high-performance, high-durability workloads."

Source: AWS Certified Solutions Architect – Official Study Guide, EBS Performance section.

Amazon RDS Custom for Oracle: This service allows you to bring your own Oracle Database licenses and provides the flexibility to customize the database settings, making it suitable for applications that require privileged access and third-party database features.

BYOL (Bring Your Own License):

RDS Custom supports the BYOL model, allowing you to use your existing Oracle licenses and comply with licensing requirements.

This helps in leveraging existing investments and reducing migration costs.

Customization and Third-Party Features:

RDS Custom allows for deeper customization of the database environment compared to standard RDS instances.

This makes it possible to support the third-party features that your application relies on without significant changes.

Migration Process:

Use native Oracle tools like Data Pump or RMAN to migrate the database to RDS Custom.

Customize the database settings post-migration to ensure compatibility with third-party features.

Versioning in S3 preserves every version of every object — preventing permanent overwrites. This ensures compliance where data cannot be overwritten or lost.

SSE-S3 ensures server-side encryption.

“When you enable versioning, Amazon S3 stores every version of every object. With versioning, you can preserve, retrieve, and restore every version of every object stored in an S3 bucket.”

— S3 Versioning

This satisfies regulatory requirements for protecting data from overwriting indefinitely.

Incorrect Options:

B: Object Lock with retention period is time-bound, not indefinite.

C: Legal hold blocks deletion but doesn’t directly prevent overwriting.

D: Storage Lens is analytics, not protection.

The best practice for granting AWS service access to EC2 instances is to assign IAM roles with the least privilege necessary. IAM roles attached to EC2 instances provide temporary credentials automatically rotated by AWS, avoiding hard-coded credentials in the application code.

Option C adheres to security best practices by assigning an IAM role scoped with the minimum permissions needed to access the S3 bucket.

Option A grants administrative access, which violates least privilege principles. Options B and D use IAM users with static credentials, increasing the risk of credential exposure and requiring manual rotation, which is not recommended.

For an application requiring TCP communication and high availability:

Network Load Balancer (NLB)is the best choice for load balancing TCP traffic because it is designed for handling high-throughput, low-latency connections.

Auto Scaling groupensures that the application can automatically scale based on demand, adding or removing EC2 instances as needed, which is crucial for handling user growth.

Option C (Application Load Balancer): ALB is primarily for HTTP/HTTPS traffic, not ideal for TCP.

Option D (Manual scaling): Manually adding instances does not provide the automation or scalability required.

Option E (Gateway Load Balancer): GLB is used for third-party virtual appliances, not for direct application load balancing.

AWS References:

Network Load Balancer

Auto Scaling Group

AWS recommends using Amazon ElastiCache as an in-memory caching layer in front of relational databases such as Amazon RDS to offload read traffic and significantly improve performance for read-heavy workloads. ElastiCache (Redis OSS) provides microsecond latency and can cache the results of frequent or expensive queries without requiring any change to the underlying database schema or engine. This directly addresses the requirement to improve performance without changing the database structure and with minimal operational overhead, because ElastiCache is a fully managed service (patching, failure detection, replacement, etc., are handled by AWS).

Option A (DynamoDB) would require a full data migration and application changes, including schema and query rewrites.

Option C (Memcached on EC2) introduces additional management overhead for EC2 instances (scaling, patching, HA).

Option D (DAX) is a caching layer only for DynamoDB and cannot be used directly with Amazon RDS.

A Network Load Balancer operates at Layer 4 (TCP/UDP/TLS) and is optimized for high performance and static IP use cases. While NLB target groups can perform health checks, they are typically oriented around basic reachability and do not provide the same application-layer (Layer 7) visibility as an Application Load Balancer (ALB). The problem statement says the NLB is “not detecting HTTP errors,” which indicates the health signal needs to be based on an HTTP endpoint that can reflect application correctness (for example, returning specific HTTP status codes).

Replacing the NLB with an ALB enables true HTTP/HTTPS health checks against a URL path, including interpretation of HTTP response codes. This is the cleanest managed approach to detect application-layer failure modes that still allow TCP connections but produce bad HTTP responses. Once the ALB detects targets as unhealthy, the target group health status can be used by an Auto Scaling group to take action. With appropriate health check configuration (and, commonly, using ELB health checks as a signal), Auto Scaling can replace unhealthy instances automatically, improving availability without custom scripts.

Option A is misleading: NLB does not provide the same HTTP-aware request routing and rich L7 features; even if an NLB health check is configured, it does not address the broader need for application-layer detection and remediation as directly as ALB. Option B violates the “no custom scripts” requirement. Option D reacts to UnhealthyHostCount, but if the NLB isn’t marking hosts unhealthy for HTTP error cases, the metric won’t reliably trigger replacement; it also still depends on the NLB’s limited visibility into HTTP failures.

Therefore, C best meets the requirement by shifting to ALB for application-layer health checks and using Auto Scaling to replace unhealthy instances automatically.

This solution meets the company's requirements with minimal administrative overhead and ensures security and ease of management.

AWS AppConfig: AWS AppConfig is a service designed to manage application configuration in a secure and validated way. It allows you to deploy configurations safely and quickly without affecting the application's performance or availability.

AWS Secrets Manager: AWS Secrets Manager is specifically designed to manage, retrieve, and rotate credentials for databases and other services. It integrates seamlessly with AWS services like Amazon RDS, making it an ideal solution for securely storing and retrieving database credentials. Secrets Manager also provides automatic rotation of credentials, reducing the operational burden.

Why Not Other Options?:

Option B (AWS Lambda + Parameter Store): While AWS Lambda can be used for managing configurations and AWS Systems Manager Parameter Store can store credentials, this approach involves more manual setup and does not offer the same level of integrated management and security as AppConfig and Secrets Manager.

Option C (Encrypted S3 Configuration File): Storing configuration and credentials in S3 files involves more manual management and security considerations, increasing the administrative overhead.

Option D (AppConfig + RDS for credentials): RDS is not designed for storing application credentials; it's better suited for managing database instances and their configurations.

AWS References:

AWS AppConfig- Describes how to use AWS AppConfig for managing application configurations.

AWS Secrets Manager- Provides details on securely storing and retrieving credentials using AWS Secrets Manager.

EC2 instances in private subnets cannot access the internet unless there is a NAT gateway or a NAT instance configured.

“To enable instances in a private subnet to connect to the internet or other AWS services, you can use a NAT gateway or NAT instance.”

— NAT Gateways – Amazon VPC

In this use case:

EC2 instances are in private subnets

They need to call external APIs (internet access)

The most operationally efficient and secure method is to place a NAT Gateway in a public subnet and update the route table for private subnets to route internet-bound traffic through it.

Incorrect Options:

A: Private subnets don’t support public IPs.

C: VPC peering doesn’t help reach the public internet.

D: Interface endpoints are for private connectivity to AWS services, not external APIs.

Since the workload is interruptible and can resume after restarts, Amazon EC2 Spot Instances are the most cost-effective option, offering savings of up to 90% compared to On-Demand. Running the batch workload on AWS Batch with Spot Instances allows automatic job queue management, interruption handling, and scheduling. Option A and C reduce cost but still rely on reserved or committed pricing for On-Demand capacity. Option B (Capacity Reservations) increases cost instead of reducing it. Therefore, the most cost-optimized solution is D — AWS Batch with EC2 Spot Instances.

For cost-effectiveness and high availability in Amazon EMR workloads, the best approach is to configure atransient cluster(which runs for the duration of the job and then terminates) withOn-Demand Instancesfor the primary and core nodes, andSpot Instancesfor the task nodes. Here's why:

Primary and core nodes on On-Demand Instances: These nodes are critical because they manage the cluster and store data on HDFS. Running them on On-Demand Instances ensures stability and that no data is lost, as Spot Instances can be interrupted.

Task nodes on Spot Instances: Task nodes handle additional processing and can be used with Spot Instances to reduce costs. Spot Instances are much cheaper but can be interrupted, which is fine for non-critical tasks as the framework can handle retries.

Atransient clusteris more cost-effective than a long-running cluster for workloads that only run for 6 hours a day. Transient clusters automatically terminate after the workload completes, saving costs by not keeping the cluster running when it's not needed.

Option A: A long-running cluster may result in unnecessary costs when the cluster isn't being used.

Option C: Running core nodes on Spot Instances risks data loss if the Spot Instances are interrupted, violating the requirement for zero data loss.

Option D: Running both core and task nodes on Spot Instances is highly risky for data-critical workloads.

AWS References:

Amazon EMR Cluster Management

Using Spot Instances in EMR

This solution offers the least operational overhead while meeting the security and global availability requirements:

Amazon CloudFront and S3: Hosting the static frontend on S3 and serving it via CloudFront provides low-latency global distribution, high availability, and security. S3 is a cost-effective and serverless option for hosting static assets, and CloudFront ensures that the application is cached closer to the users, reducing latency globally.

AWS Lambda and API Gateway: Refactoring the microservices to use Lambda functions with API Gateway allows for a fully serverless, scalable, and highly available backend. This reduces the need for managing EC2 instances, as Lambda automatically scales to meet demand and only charges for the actual usage.

RDS for MySQL: Migrating the MySQL database from an EC2 instance to Amazon RDS significantly reduces operational overhead. RDS manages backups, patching, and scaling, and it offers high availability options (e.g., Multi-AZ).

Option AandDinvolve using EC2 Reserved Instances for the database, which requires more operational maintenance than using RDS.

Option Csuggests using a Network Load Balancer with Lambda, which adds unnecessary complexity for this use case.

AWS References:

Amazon S3 and CloudFront Integration

AWS Lambda with API Gateway

Amazon RDS for MySQL

The company needs a cloud-based storage solution for frequently accessed data with low latency, while retaining their current on-premises infrastructure for some data storage. AWS Storage Gateway'sVolume Gateway with cached volumesis the most appropriate solution for this scenario.

AWS Storage Gateway - Volume Gateway (Cached Volumes):

Volume Gateway with cached volumesallows you to store frequently accessed data in the AWS Cloud while keeping the most recently accessed data cached locally on-premises. This ensures low-latency access to active data while providing scalability for the rest of the data in the cloud.

The cached volume option stores the primary data in Amazon S3 but caches frequently accessed data locally, ensuring fast access. This configuration is well-suited for applications that require fast access to frequently used data but can tolerate cloud-based storage for the rest.

Since the company is facing limited on-premises storage, cached volumes provide an ideal solution, as they reduce the need for additional on-premises storage infrastructure.

Why Not the Other Options?:

Option A (S3 File Gateway): S3 File Gateway provides a file-based interface (SMB/NFS) for storing data directly in S3. While it is great for file storage, the company’s need for block-level storage with iSCSI targets makes Volume Gateway a better fit.

Option C (Volume Gateway - Stored Volumes): Stored volumes keep all the data on-premises and asynchronously back up to AWS. This would not address the company's storage limitations since they would still need substantial on-premises storage.

Option D (Tape Gateway): Tape Gateway is designed for archiving and backup, not for frequently accessed low-latency data.

AWS References:

AWS Storage Gateway - Volume Gateway

Compute Savings Plansoffer the most flexible and cost-effective solution for the production instances, as they provide significant savings (up to 66%) for both EC2 and AWS Lambda usage, while allowing flexibility in the type of instance family, size, and even region. For nonproduction instances, usingOn-Demand Instancesensures you only pay for the instances when they are running, and shutting them down during off-hours further optimizes cost.

Key AWS features:

Compute Savings Plans: Provide savings based on consistent usage, making it ideal for production environments with steady load.

On-Demand Instances: Suitable for nonproduction environments that are used intermittently. Shutting them down when not in use avoids unnecessary costs.

AWS Documentation: According to AWS's cost optimization best practices, using a combination of Savings Plans for production and On-Demand Instances for nonproduction environments that are used sparingly results in optimal cost savings​​.

When using imported key material with AWS KMS, you maintain control over the key lifecycle. AWS KMS allows you to import new key material into an existing KMS key (of type "external" or "imported"), thus rotating the key material without changing the key ID or ARNs. This enables applications to continue using the same key for cryptographic operations without disruption.

You can also set an expiration time for the old key material, after which AWS KMS deletes the old material and requires new key material to be imported, enforcing regular rotation per your compliance requirements.

AWS Documentation Extract:

"To rotate imported key material, you can re-import new key material into the same KMS key. This retains the same key ID and ARNs so applications are unaffected. You can set an expiration time for imported key material and replace it as needed, ensuring compliance with your rotation policy."

(Source: AWS Key Management Service Developer Guide, Importing Key Material, Rotating Key Material)

Other options:

A: You cannot create a new KMS key with the same key ID as an existing one.

B: Deleting and recreating the key disrupts application access because the key ID changes.

D: Automatic rotation is only available for AWS-managed keys, not for imported key material.

D is the best match because AWS Lambda is a serverless compute service that runs code without provisioning or managing servers, which directly aligns with the requirement for minimal infrastructure and minimal operational support. Lambda supports Python runtimes, so the team can deploy the selected component as a microservice using the same language. For workloads with hundreds of requests per second, Lambda is designed to handle request-driven execution and automatically scales by running more concurrent instances of the function in response to incoming traffic, without the customer needing to pre-size or manage capacity.

The other options introduce significantly more operational responsibility. Option A still requires managing EC2 instances (AMI lifecycle, patching, capacity planning, scaling policies) and Spot interruptions can add complexity for a web microservice test. Option B (Elastic Beanstalk) reduces some management overhead but still relies on underlying instances and environment management (platform updates, scaling configuration, health monitoring), and it is not a serverless model. Option C (EKS with self-managed nodes) has the highest operational burden here: cluster and node management, scaling node groups, patching, and Kubernetes operations—this conflicts with “minimal operational support.”

Lambda fits the serverless microservices goal: deploy code as small independent services, integrate with other managed services (commonly API-driven invocation patterns), and rely on AWS-managed scaling and availability mechanisms rather than administering fleets or clusters.

Amazon S3 supports one Lifecycle configuration per bucket that can contain multiple rules. Lifecycle rules can include filters, including object size filters: ObjectSizeGreaterThan and ObjectSizeLessThan. You can combine rules so that one targets large objects and another provides a default expiration. Here, configure Rule 1 with a size filter ObjectSizeGreaterThan = 1 TB and Expiration = 2 days (48 hours) to purge very large videos early. Configure Rule 2 with Expiration = 7 days without a size filter to serve as a catch-all maximum retention for all objects. Options B and D are invalid because S3 does not allow multiple Lifecycle configurations per bucket. Option C cannot distinguish large files; it would delete all files at the same schedule without honoring the 48-hour policy for >1 TB objects. This single configuration with two rules meets both retention targets with minimal overhead and full S3-native capability.

The Application Load Balancer (ALB) supports sticky sessions (session affinity) using application cookies. AWS WAF integrates natively with ALB to provide Layer 7 protection at the same endpoint.

From AWS Documentation:

“You can enable sticky sessions for your Application Load Balancer target groups to ensure that a user’s requests are consistently routed to the same target. AWS WAF integrates with Application Load Balancer to protect your web applications from common exploits.”

(Source: Elastic Load Balancing User Guide & AWS WAF Developer Guide)

Why C and E are correct:

C: ALB operates at Layer 7 (HTTP/HTTPS), supports sticky sessions, and can serve as a public endpoint.

E: AWS WAF can be directly associated with the ALB to inspect traffic and enforce rules.Together, they fulfill both the security and session affinity requirements.

Why others are incorrect:

A: Network Load Balancer doesn’t support session affinity.

B: Gateway Load Balancer is used for virtual appliances, not web applications.

D: Using EIPs bypasses load balancing and WAF integration.

AWS KMS automatic key rotationis the simplest and most operationally efficient solution. Enabling automatic key rotation ensures that KMS automatically generates new key material for the key every year without requiring manual intervention.

Option B:Configuring alerts to rotate keys introduces operational overhead as the actual rotation must still be managed manually.

Option C:Scheduling a Lambda function to rotate keys adds unnecessary complexity compared to enabling automatic key rotation.

Option D:Using a CloudFormation stack to run a Lambda function for key rotation increases operational overhead and complexity unnecessarily.

AWS Documentation References:

AWS KMS Key Rotation

Using Customer-Managed Keys with Amazon RDS

Amazon FSx for Lustre is a high-performance parallel file system designed for machine learning and HPC that can be linked to Amazon S3 via Data Repository Associations (DRA). With DRA, you can import S3 objects as files (lazy or preloaded) and export results back to S3, providing very high throughput and low-latency POSIX access on the training cluster. This S3-native integration minimizes data loading overhead and accelerates training cycles at scale. EFS (A) is general-purpose and lower throughput per TB than Lustre. EBS (C) requires manual copy and does not scale as a shared parallel filesystem. DataSync alone (D) is a transfer tool, not a high-throughput training filesystem. FSx for Lustre with S3 DRA best satisfies scalability, throughput, and native S3 integration for rapid ML training.

Amazon DocumentDB global clusters support managed cross-region failover, allowing you to promote a secondary region to become the new primary with minimal downtime. This ensures business continuity during maintenance or regional disruptions.

Reference Extract:

"Amazon DocumentDB global clusters support managed cross-Region failover, allowing you to recover quickly from regional disruptions with minimal downtime."

Source: AWS Certified Solutions Architect – Official Study Guide, DocumentDB and Resiliency section.

AWS Secrets Manager is the recommended service for storing database credentials and performing automated rotation. Any Lambda function version or alias can fetch the latest secret value at runtime, ensuring no outdated credentials exist in deployed versions.

Environment variables (Option C) are static per version. Embedding credentials in code (Option B) is insecure and requires redeployment. Parameter Store (Option D) supports rotation but requires more configuration and is not as seamless as Secrets Manager for database credential rotation.

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AWS WAF (Web Application Firewall): AWS WAF allows you to create custom rules to block or allow web requests based on conditions that you specify.

Web ACL (Access Control List):

Create a web ACL and associate it with the ALB.

Use IP rule sets to specify the IP addresses of the retail locations that are allowed to access the application.

Security and Flexibility:

AWS WAF provides a scalable way to manage access control, ensuring that only traffic from registered IP addresses is allowed.

You can dynamically update the IP rule sets to add or remove IP addresses as needed.

Operational Simplicity: Using AWS WAF with a web ACL is straightforward and integrates seamlessly with the ALB, providing an efficient solution for managing access control based on IP addresses.

The best practice for granting AWS resource access to EC2 instances is to use IAM roles, not users or long-lived access keys. You create an IAM role with a policy that grants the minimum permissions required, then attach that role to an instance profile associated with the EC2 instance. The instance then automatically receives temporary credentials for AWS service access.

AWS Documentation Extract:

"Attach an IAM role to your EC2 instances to securely grant permissions to AWS services according to the principle of least privilege. Never embed access keys in EC2 instances."

(Source: AWS EC2 documentation, IAM Roles for EC2)

A, B: Using IAM users and embedding keys violates security best practices.

C: IAM role credentials are automatically managed and never need to be manually attached as keys.

Amazon RDS Proxy is designed to manage a large number of database connections from applications, especially serverless applications that can scale quickly. It improves application availability and scalability by pooling and sharing established database connections. This reduces the overhead of database connections and prevents overload during traffic spikes.

Aurora blue/green deployments are specifically designed for:

Safely testing schema changes and database upgrades in an isolated environment (green) without impacting production (blue).

Performing a fast, low-downtime switchover once testing is complete and validated.

In this pattern:

The blue environment is the current production database.

The green environment is a synchronized copy used for testing changes.

You apply schema changes to the green environment, run tests, and when ready, perform a managed switchover that minimizes downtime and risk.

Why others are not ideal:

A: A separate staging cluster allows testing but does not provide automated, low-downtime synchronization and switchover.

B: Aurora read replicas are for read scaling; schema changes on replicas are not supported in the way described, and promotion alone doesn’t solve controlled testing and replication of changes.

D: Moving to DynamoDB changes database engines and data models entirely, and does not match the requirement to keep using Aurora MySQL.

Auto Scalingis the most effective solution for ensuring seamless scalability of a stateless application. Key points:

Dleverages Auto Scaling with a Spot Fleet for cost efficiency and attaches an ALB to distribute traffic.

A and Bdo not provide automated scaling and would require manual intervention to add more instances.

Cchanges the instance type but does not scale out horizontally, which is required here.

AWS Documentation Reference:

Amazon EC2 Auto Scaling

S3 Intelligent-Tiering is designed for data with unknown or changing access patterns. It automatically moves objects between frequent and infrequent access tiers as needed, with no retrieval fees for accessing data in any tier, and no performance impact. Minimal management overhead is required because AWS manages all transitions automatically. This class is cost-optimized and meets all requirements listed.

AWS Documentation Extract:

"S3 Intelligent-Tiering is the only storage class that automatically moves data between frequent and infrequent access tiers when access patterns change, with no retrieval charges and no impact on performance. It is designed to optimize costs automatically when data access patterns are unpredictable."

(Source: Amazon S3 documentation, Intelligent-Tiering storage class)

Other options:

B: Storage class analysis only provides recommendations, not actual storage tiering.

C & D: S3 Standard-IA and S3 One Zone-IA both have retrieval fees and may impact retrieval time and data durability.

Amazon ElastiCache (Redis OSS) provides an in-memory cache that drastically improves read performance with minimal operational overhead.

It integrates easily with RDS and does not require schema or database changes.

EC2-based caching (Option C) increases management overhead.

DAX (Option D) accelerates DynamoDB only, not RDS.

Moving to DynamoDB (Option A) requires complete application and schema redesign.

=====================================================

The requirement is an event-driven pub/sub system that guarantees ordered delivery of events.

Amazon SNS FIFO topics provide the publish-subscribe model along with FIFO (First-In-First-Out) delivery and exactly-once message processing, ensuring ordered delivery to multiple subscribers.

Option A, EventBridge, provides event buses but does not guarantee event ordering across multiple subscribers. Option C (SNS standard topics) provides pub/sub but without ordering guarantees. Option D (SQS FIFO queues) guarantees order but are point-to-point queues, not pub/sub.

Thus, Amazon SNS FIFO topics meet the requirements for ordered pub/sub messaging.

This question centers on improving scalability and global access performance.

Auto Scaling groups enable EC2 instances to scale dynamically in response to demand, ensuring availability during peak hours without manual intervention. Amazon RDS read replicas offload read traffic, improving read throughput and reducing latency on the primary database instance. Deploying Amazon CloudFront with S3 as origin accelerates delivery of static transaction documents globally by caching content at edge locations, reducing latency for users worldwide.

Option B focuses on vertical scaling (larger instances) and caching with ElastiCache, but it does not address global content delivery optimally. AWS Global Accelerator accelerates network traffic but is better suited for accelerating TCP and UDP traffic; CloudFront is generally preferred for HTTP content delivery.

Option C migrates workloads to Lambda and Aurora global databases, which is an advanced and potentially costly redesign that may not be necessary. Option D suggests moving to ECS and multi-AZ RDS but does not address global content delivery efficiently.

Therefore, option A uses proven scalability and caching best practices aligned with AWS Well-Architected Framework pillars for performance and operational excellence.

AWS WAF has limits on how much of an HTTP request body it can inspect. When requests exceed the inspectable size, AWS WAF treats the body as oversize relative to the configured inspection limits, which can lead to rules not evaluating the entire body content. If suspicious payloads are embedded beyond the inspected portion of a large POST request (for example, > 8 MB), WAF cannot reliably detect them purely through body inspection rules.

Given this constraint, the most effective way to “ensure” proper protection is to implement an oversize handling strategy using AWS WAF rule logic: block oversized requests by default and then explicitly allow oversized requests only from known legitimate sources. Option A accomplishes this by adding a rule that blocks oversize requests (so attackers cannot bypass inspection by sending very large bodies) and a higher-priority allow rule to permit large requests from trusted hosts (for example, specific known partners, internal CIDRs, or authenticated upstream systems). This design reduces the attack surface and provides deterministic behavior for requests that cannot be fully inspected.

Option B is incorrect because Shield Advanced is for DDoS protection and does not extend WAF’s request-body inspection size. Option C is unrelated: Content-Type can influence application parsing, but it will not overcome WAF body-size inspection limitations. Option D is not a practical fit for AWS WAF inspection because WAF evaluates requests at the edge/service layer; it does not natively “call Lambda to rewrite the request body” before WAF evaluates it. Any preprocessing would require a different architectural pattern (such as handling uploads out-of-band), which is beyond the scope and would add operational complexity.

Therefore, A is the correct approach: implement explicit oversized request handling by blocking by default and allowing only vetted large requests.

When designing a microservice architecture where each microservice interacts with different AWS services, it's essential to follow the principle of least privilege. This means granting each microservice only the permissions it needs to perform its tasks, reducing the risk of unauthorized access or accidental actions.

The recommended approach is to create individualIAM roleswith policies that grant each microservice the specific permissions it requires. Then, these roles should be associated with the EC2 instances that run the corresponding microservice. By doing so, each EC2 instance will assume its specific IAM role, and permissions will be automatically managed by AWS.

IAM roles provide temporary credentials via the instance metadata service, eliminating the need to hard-code credentials in your application code, which enhances security.

AWS References:

IAM Roles for Amazon EC2explains how EC2 instances can use IAM roles to securely access AWS services without managing long-term credentials.

Best Practices for IAMincludes recommendations for implementing the least privilege principle and using IAM roles effectively.

Why the other options are incorrect:

A. Assign an IAM user to each microservice: This requires managing long-term credentials (access keys), which should be avoided. Storing keys in application code is insecure and creates a maintenance burden.

B. Create a single IAM role: This violates the principle of least privilege, as a single role with broad permissions across all services is less secure.

C. Use AWS Organizations: This approach adds unnecessary complexity. Managing permissions at the account level for each microservice is excessive for this use case and doesn't adhere to the principle of least privilege.

ECS with Fargate: Allows containerized workloads to scale rapidly without managing underlying servers, handling unpredictable growth effectively.

RDS for Relational Data: Manages large relational datasets efficiently while supporting high availability.

SQS for Decoupling: Ensures message processing occurs in a specific order, decoupling application components and allowing independent evolution.

AWS ECS with Fargate Documentation,AWS SQS Documentation

AWS documentation states that when Lambda processes events, a dead-letter queue (DLQ) using Amazon SQS is the correct mechanism to capture failed invocations for later reprocessing.

SQS provides durable buffering and decoupling, allowing records to be retried safely without loss.

Kinesis Firehose (Option B) does not support SQL replays or arbitrary replay control. SNS (Option D) is not a durable store. OpenSearch (Option C) is not intended for durable retry queues.

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Amazon EFSwithMax I/O performance modeis designed for workloads that require high levels of parallelism, such as video processing across multiple EC2 instances. EFS provides shared file storage that can be mounted on both Windows and Linux EC2 instances, and the Max I/O mode ensures the best performance for handling large files and concurrent access across multiple instances.

Option A and B (FSx for Windows File Server): FSx for Windows File Server is optimized for Windows workloads and would not be ideal for Linux instances or high-throughput, parallel workloads.

Option D (EFS General Purpose mode): General Purpose mode offers lower latency but doesn't support the high throughput needed for large, concurrent workloads.

AWS References:

Amazon EFS Performance Modes

Amazon S3 Intelligent-Tiering is designed for data with unknown or changing access patterns. It automatically moves data between frequent and infrequent access tiers based on usage. This tier offers immediate access to all objects, regardless of which tier they are stored in, while optimizing storage costs. S3 Intelligent-Tiering also provides the same high durability, availability, and security as other S3 storage classes and supports access from external resources using standard S3 APIs. Lifecycle policies and Glacier classes are more suitable for archival when infrequent access is predictable, but retrieval from Glacier classes is not immediate and incurs extra charges and delays.

Reference Extract from AWS Documentation / Study Guide:

"S3 Intelligent-Tiering is designed to optimize costs by automatically moving data between two access tiers when access patterns change. Data is always available and immediately accessible, making it ideal for unknown or unpredictable access patterns."

Source: AWS Certified Solutions Architect – Official Study Guide, S3 Storage Classes section.

Amazon S3 Standard provides virtually unlimited scalability, high durability (11 nines), and millisecond latency. It is designed for storing large volumes of unstructured content such as media files. S3 also supports pre-signed URLs and direct browser uploads, enabling users to upload files securely without passing through backend servers. EBS volumes (A) are block storage, limited to single AZ, and not suitable for web-scale storage. EFS (B) is a shared file system for POSIX workloads, not for direct browser uploads. S3 Express One Zone (D) offers higher performance for small objects but does not provide cross-AZ durability, making it unsuitable for growing global content. Therefore, option C is the most scalable, durable, and cost-effective solution.

Key Requirements:

Serverless architecture.

Handle traffic bursts with high availability.

Process orders asynchronouslyin the order they are received.

Analysis of Options:

Option A:Amazon SNS delivers messages to subscribers. However, SNS does not ensure ordering, making it unsuitable for FIFO (First In, First Out) requirements.

Option B:Amazon SQS FIFO queues support ordering and ensure messages are delivered exactly once. AWS Lambda functions can be triggered by SQS to process messages asynchronously and efficiently. This satisfies all requirements.

Option C:Amazon SQS standard queues do not guarantee message order and have "at-least-once" delivery, making them unsuitable for the FIFO requirement.

Option D:Similar to Option A, SNS does not ensure message ordering, and using AWS Batch adds complexity without directly addressing the requirements.

AWS References:

Amazon SQS FIFO Queues

AWS Lambda and SQS Integration

The requirements specify capturing unpredictable and sudden spikes in customer activity, integrating easily with other web applications, and including authorization.

Amazon API Gateway with Lambda authorizer provides a secure, scalable entry point with flexible authorization mechanisms including token validation.

Amazon Kinesis Data Firehose is a fully managed service to reliably load streaming data into destinations such as Amazon S3, which fits well for capturing streaming customer activity data.

API Gateway integrates natively with Firehose for direct ingestion.

This combination supports unpredictable traffic, smooth scaling, and simple authorization.

Option B uses Kinesis Data Streams, which requires more management than Firehose and is less optimized for direct API integration. Options A and D use Gateway Load Balancer and ECS containers plus EFS, which add complexity and are less suited for unpredictable traffic with integrated authorization.

Amazon Elastic File System (EFS) is a managed file storage service that can be mounted across multiple EC2 instances. It provides a scalable and high-performing solution to share data among instances within a VPC.

High Performance: EFS provides scalable performance for workloads that require high throughput and IOPS. It is particularly well-suited for applications that need to share data across multiple instances.

Ease of Use: EFS can be easily mounted on multiple instances across different Availability Zones, providing a shared file system accessible to all the instances within the VPC.

Security: EFS can be configured to ensure that data remains within the VPC, and it supports encryption at rest and in transit.

Why Not Other Options?:

Option A (Amazon S3 bucket with APIs): While S3 is excellent for object storage, it is not a file system and does not provide the low-latency access required for shared data between instances.

Option B (S3 bucket as a mounted volume): S3 is not designed to be mounted as a file system, and this approach would introduce unnecessary complexity and latency.

Option C (EBS volume shared across instances): EBS volumes cannot be attached to multiple instances simultaneously. It is not designed to be shared across instances like EFS.

AWS References:

Amazon EFS- Overview of Amazon EFS and its features.

Best Practices for Amazon EFS- Recommendations for using EFS with multiple instances.

AWS STS issues temporary credentials with automatically expiring permissions based on IAM roles. This eliminates the need to manually manage or deactivate IAM users.

“You can use AWS STS to grant temporary security credentials that automatically expire after a specified duration.”

— Temporary Security Credentials

This is the least operational overhead and follows AWS best practices for short-term access.

AWS recommends using AWS IAM Identity Center (formerly AWS SSO) for centralized authentication and access control across multiple accounts in an AWS Organization, especially when integrating with an external IdP.

From AWS Documentation:

“Use IAM Identity Center to provide centralized access to multiple AWS accounts or applications. You can integrate with an external IdP via SAML 2.0. Assign users permissions through permission sets that define the roles users can assume.”

(Source: AWS IAM Identity Center User Guide)

Why B and E are correct:

E enables centralized identity federation using IAM Identity Center with your external IdP.

B uses permission sets to apply least-privilege access roles to users and groups across accounts, in alignment with the principle of least privilege.

Why others are incorrect:

Option A: IAM users in each account break centralized access model and are hard to manage at scale.

Option C: Managing individual IAM roles and inline policies across accounts is not scalable.

Option D: Per-account SAML providers are redundant when using IAM Identity Center, which provides centralized federation.

The best solution to enforce encryption at rest for Amazon EBS volumes is to use anIAM policyto restrict the creation of unencrypted volumes. To automatically identify and remediate unencryptedvolumes, you can useAWS Configrules, which continuously monitor the compliance of resources, andAWS Systems Managerto automate the remediation by encrypting existing unencrypted volumes. This setup requires minimal administrative overhead while ensuring compliance.

Option B (KMS): KMS is for managing encryption keys, but Config and Systems Manager provide a better solution for automatic detection and enforcement.

Option C (Macie): Macie is for data classification and is not suitable for this use case.

Option D (Inspector): Inspector is used for security vulnerabilities, not encryption compliance.

AWS References:

AWS Config Rules

AWS Systems Manager

Amazon Aurora Serverless is a cost-effective, on-demand, autoscaling configuration for Amazon Aurora. It automatically adjusts the database's capacity based on the current demand, which is ideal for workloads with variable and unpredictable usage patterns. Since the application is expected to be read-heavy with occasional writes and steady growth, Aurora Serverless can provide the necessary performance without requiring the management of database instances.

Cost-Optimization: Aurora Serverless only charges for the database capacity you use, making it a more cost-effective solution compared to always running provisioned database instances, especially for workloads with fluctuating demand.

Scalability: It automatically scales database capacity up or down based on actual usage, ensuring that you always have the right amount of resources available.

Performance: Aurora Serverless is built on the same underlying storage as Amazon Aurora, providing high performance and availability.

Why Not Other Options?:

Option A (RDS with Provisioned IOPS SSD): While Provisioned IOPS SSD ensures consistent performance, it is generally more expensive and less flexible compared to the autoscaling nature of Aurora Serverless.

Option C (DynamoDB with On-Demand Capacity): DynamoDB is a NoSQL database and may not be the best fit for applications requiring relational database features.

Option D (RDS with Magnetic Storage and Read Replicas): Magnetic storage is outdated and generally slower. While read replicas help with read-heavy workloads, the overall performance might not be optimal, and magnetic storage doesn’t provide the necessary performance.

AWS References:

Amazon Aurora Serverless- Information on how Aurora Serverless works and its use cases.

Amazon Aurora Pricing- Details on the cost-effectiveness of Aurora Serverless.

S3 Block Public Access only blocks public access—not explicitly allowed access.

An S3 bucket policy can explicitly permit access only from specific source IP addresses using the aws:SourceIp condition. This allows secure, direct HTTP access to the S3 object from known firewall IP addresses.

Static website hosting (Option A) requires the bucket to be public and is blocked by the enabled S3 Block Public Access setting.

CloudFront with OAC (Option C) is unnecessary and adds cost and complexity.

Lambda (Option D) introduces operational overhead and is not needed since S3 policies can enforce IP restrictions directly.

Express Workflows in AWS Step Functions are optimized for high-throughput, short-duration, and low-cost workflows. They are suitable for applications with large volumes of parallel and interdependent tasks. When paired with HTTP APIs from API Gateway, which are more cost-efficient than REST APIs, this setup offers scalability and cost-effectiveness.

Why Option D is Correct:

IAM Roles with Instance Profiles: Allow applications to access AWS services securely without hardcoding long-term access keys.

Short-Term Credentials: IAM roles issue short-term credentials dynamically managed by AWS.

Why Other Options Are Not Ideal:

Option A and B: Embedding or retrieving long-term access keys introduces security risks and operational overhead.

Option C: Combining IAM roles with Parameter Store adds unnecessary complexity.

AWS References:

IAM Roles and Instance Profiles:AWS Documentation - IAM Roles

AWS advises using serverless event-driven processing to minimize operational burden and scale automatically with demand. Amazon SQS can be directly configured as an event source for AWS Lambda. With this setup, Lambda polls the queue, invokes the function, and processes messages without requiring the customer to manage infrastructure. Scaling is automatic, based on the volume of messages in the queue. Option A (increasing instance size) still leaves scaling and management challenges. Option B reduces cost when idle but does not address scaling. Option D requires manual triggering and does not meet continuous processing requirements. Migrating the script to Lambda (C) fully eliminates the need for instance management, providing scalability, reliability, and reduced operational overhead.

The ALB must be in a public subnet to receive internet traffic. The EC2 instances and the RDS database should be in private subnets to prevent direct internet access, minimizing the attack surface. This aligns with AWS security best practices for web application architectures.

Reference Extract:

"Internet-facing ALBs should be placed in public subnets; EC2 instances and RDS databases should be in private subnets to restrict direct internet access."

Source: AWS Certified Solutions Architect – Official Study Guide, Network Security and Design section.

Pre-Signed URLs: Allow temporary access to S3 buckets, making it easy to manage time-limited upload permissions without complex operational overhead.

Lambda for Automation: Automatically generates and provides pre-signed URLs when users authenticate, minimizing manual steps and code complexity.

Least Operational Overhead: Requires no custom authentication service or deep integration with STS or Cognito.

Amazon S3 Pre-Signed URLs Documentation

AWS Direct Connect provides a dedicated network connection from on-premises to AWS, offering greater bandwidth and more consistent performance than internet-based connections or VPN. AWS PrivateLink enables secure, private connectivity to supported AWS services such as Kinesis Data Firehose over Direct Connect, bypassing the public internet and providing the highest throughput and lowest latency possible. This is the recommended solution for consistently transferring large volumes of data with maximum reliability and performance.

Reference Extract from AWS Documentation / Study Guide:

"AWS Direct Connect and AWS PrivateLink provide private, high-throughput connectivity between on-premises and AWS services, bypassing the public internet and ensuring maximum performance for large data transfers."

Source: AWS Certified Solutions Architect – Official Study Guide, Hybrid Networking section.

AmazonSES (Simple Email Service)allows for the automatic ingestion of incoming emails. By setting up email receiving in SES and creating a rule set with a receipt rule, you can configure SES to invoke anAWS Lambda functionwhenever an email is received. The Lambda function can then process the email body and attachments, saving any attachments to an Amazon S3 bucket. This solution is highly scalable, cost-effective, and provides near real-time processing of emails with minimal operational overhead.

Option B (Content filtering): This only filters emails based on content and does not provide the functionality to save attachments to S3.

Option C (S3 Event Notifications): While SES can store emails in S3, SES with Lambda offers more flexibility for processing attachments in real-time.

Option D (EventBridge rule): EventBridge cannot directly listen for incoming emails, making this solution incorrect.

AWS References:

Receiving Email with Amazon SES

Invoking Lambda from SES

The IAM policy includes two statements:

1️⃣ Allow ec2:TerminateInstances on all resources

2️⃣ Deny ec2:TerminateInstances if the request does NOT come from:

192.0.2.0/24

203.0.113.0/24

AWS IAM policy evaluation rules state:

Explicit Deny always overrides Allow.

A request must meet all applicable conditions in the policy to be granted.

aws:SourceIp condition applies when IAM actions are invoked via the public AWS APIs.

In this scenario, the administrator is not originating the request from one of the allowed CIDR blocks, so the Deny condition is triggered, overriding the Allow statement.

Therefore, the operation is blocked with:

403 AccessDenied: explicit deny

This matches the behavior described in the AWS IAM Policy Evaluation Logic used in the Security Pillar of the Well-Architected Framework:

Explicit Deny > Allow > Default Deny

IP-based Conditions restrict API calls originating outside approved network ranges

Options A/B/C do not accurately reflect this explicit Deny condition behavior.

According to the AWS Well-Architected Framework – Security Pillar and the AWS Identity and Access Management (IAM) User Guide, the root user account in an AWS account is extremely powerful and should be protected with strict security measures.

From AWS documentation:

“We recommend that you not use the root user for everyday tasks, even administrative ones. Instead, create IAM users and grant them only the permissions they need. To help protect your AWS account, enable multi-factor authentication (MFA) for the root user.”

(Source: AWS Identity and Access Management User Guide – Securing the Root User)

The correct and recommended action is to create IAM users with specific permissions for daily operations and enable MFA on the root user to provide an additional layer of security. The root user cannot be disabled, so Option A is technically incorrect. AWS also explicitly advises against using root access keys (Option C) or sharing root credentials (Option D), both of which violate the principle of least privilege.

Best practices summarized from AWS official documentation:

Do not use root user for routine tasks

Enable MFA for root user immediately

Create individual IAM users and assign least privilege

Avoid creating or using root user access keys

These recommendations are foundational to securing any new AWS account and are consistently emphasized in the AWS Certified Solutions Architect – Official Study Guide and the AWS Security Best Practices whitepaper.

AWS Snowball Edge is specifically designed for use cases that involve limited or unreliable network connectivity. It enables data transfer and local compute processing at edge locations.

It comes in two options: Snowball Edge Storage Optimized and Snowball Edge Compute Optimized.

The Compute Optimized model allows the disaster response team to both store images locally and process data on the device using Amazon EC2-compatible compute resources.

This removes the need for constant network connectivity. After processing, the device can be shipped back to AWS, where data is uploaded to S3.

Other options fail due to:

SQS not being suitable for large binary image data (Option B)

Kinesis Data Firehose needing steady connectivity (Option C)

Storage Gateway is for hybrid cloud environments with ongoing connection, not rugged field use (Option D)

???? References:

AWS Snowball Edge Overview

Snowball Edge Use Cases

Amazon EMR allows the creation of security configurations to specify settings for encrypting data at rest, data in transit, or both. These configurations can be applied to clusters to ensure that data stored in Amazon S3, local disks, and data moving between nodes is encrypted.

By creating and applying an EMR security configuration, the company can ensure that all data processing complies with encryption requirements for sensitive patient data.

This solution directly addresses the scalability and high availability requirements with minimal downtime.

Additional Reader Instances: Adding more reader instances to the Aurora cluster will distribute the read load, improving the performance of the application under heavy read traffic. Aurora reader instances automatically replicate the data from the writer instance, enabling you to scale out read operations.

Amazon RDS Proxy: RDS Proxy improves database availability by managing database connections more efficiently and providing a connection pool. This reduces the overhead on the Aurora cluster during peak loads, further enhancing performance and availability without requiring changes to the application code.

Why Not Other Options?:

Option A (EventBridge and Lambda): This doesn’t directly address the performance and availability issues. Logging state changes and adding reader nodes on failure events doesn’t provide proactive scalability.

Option B (Zero-Downtime Restart and Activity Streams): Zero-Downtime Restart (ZDR) is useful for minimizing downtime during maintenance but doesn’t directly improve scalability. Database Activity Streams are more for security monitoring than for performance enhancement.

Option D (ElastiCache for Redis): While adding a caching layer can help with read performance, it introduces complexity and may not be necessary if additional reader instances can handle the load.

AWS References:

Amazon Aurora Scaling- Information on scaling Aurora clusters with reader instances.

Amazon RDS Proxy- Details on how RDS Proxy can improve database performance and availability.

Amazon Rekognition provides pretrained models that can detect inappropriate or unsafe content (such as nudity or violence) without requiring users to build their own ML models. Using a Lambda function to call Rekognition when new photos are uploaded is a serverless and scalable solution.

AWS Backup Audit Manager automates auditing and reporting of backup activity and compliance, while AWS Config provides visibility into configuration changes. Together, they provide the simplest, most automated, and compliant backup monitoring solution.

From AWS Documentation:

“AWS Backup Audit Manager automatically audits backup activity across AWS resources. You can use predefined or custom frameworks to monitor backup compliance and encryption status.”

(Source: AWS Backup Audit Manager User Guide)

Why D is correct:

Ensures centralized visibility into all backup jobs.

Verifies encryption status automatically.

Generates ready-to-use reports with minimal operational overhead.

Complies with regulatory requirements for data protection.

Why others are incorrect:

A & C: Custom Lambda automation increases maintenance effort.

B: Manual checking is operationally inefficient and error-prone.

A. Mutual TLS:Provides secure communication but does not integrate with AWS credential exchange.

B. AWS Signature v4:Requires direct integration with AWS and is less secure for external systems.

C. Kerberos:Not natively supported for AWS API authentication.

D. IAM Roles Anywhere:Enables AWS API access using X.509 certificates without long-term credentials.

AWS Key Management Service (AWS KMS) provides multi-Region keys, allowing the same key to be used across Regions without managing your own hardware or key replication.

Multi-Region keys are fully managed and support attribute-based access control (ABAC) using tags and condition keys.

CloudHSM (Options C and D) requires full key lifecycle management, synchronization, and hardware operations, resulting in significantly higher overhead.

Imported key material (Option B) increases key-management responsibility.

=====================================================

Amazon EFS provides a fully managed, highly available, and shared file system that can be mounted by instances across multiple Availability Zones. This ensures consistency of files between EC2 instances and avoids replication issues. EBS volumes, in contrast, are AZ-scoped and not designed for multi-instance sharing. Options A and B rely on custom replication or manual file handling, which increases operational overhead and risks inconsistencies. Option D does not solve the shared access and consistency requirement. By migrating storage to EFS, both EC2 instances will read and write to the same storage system, ensuring that users always access the latest files without 404 errors.

AWS Config is a service that enables you to assess, audit, and evaluate the configurations of your AWS resources. By creating a Config rule, you can automatically check whether your Amazon EBS volumes are encrypted and flag those that are not, with minimal cost and configuration effort.

AWS Config Rule: AWS Config provides managed rules that you can use to automatically check the compliance of your resources against predefined or custom criteria. In this case, you wouldcreate a rule to evaluate EBS volumes and determine if they are encrypted. If a volume is not encrypted, the rule will flag it, allowing you to take corrective action.

Operational Overhead: This approach significantly reduces operational overhead because once the rule is in place, it continuously monitors your EBS volumes for compliance, and there’s no need for manual checks or custom scripting.

Why Not Other Options?:

Option A (Lambda with API calls and EventBridge): While this can work, it involves writing and maintaining custom code, which increases operational overhead compared to using a managed AWS Config rule.

Option B (API calls on Fargate): Running API calls on Fargate is more complex and costly compared to using AWS Config, which provides a simpler, managed solution.

Option C (IAM policy with Cost Explorer): This option does not directly enforce encryption compliance and involves manual intervention, making it less efficient and more prone to errors.

AWS References:

AWS Config Rules- Overview of AWS Config rules and how they can be used to evaluate resource configurations.

Amazon EBS Encryption- Information on how to manage and enforce encryption for EBS volumes.

Requirement Analysis: Need secure, direct connectivity from an on-premises client to an RDS cluster, accessible only when in the office.

VPC with Private Subnets: Ensures the RDS cluster is not publicly accessible, enhancing security.

Site-to-Site VPN: Provides secure, encrypted connection between on-premises office and AWS VPC.

Implementation:

Create a VPC with two private subnets.

Launch the RDS cluster in the private subnets.

Set up a Site-to-Site VPN connection with a customer gateway in the office.

Conclusion: This setup ensures secure and direct connectivity with minimal exposure, meeting the requirement for secure access from the office.

References

AWS Site-to-Site VPN:AWS Site-to-Site VPN Documentation

Amazon RDS:Amazon RDS Documentation

AWS documentation states that EC2 Auto Scaling is the recommended, cost-effective, and fault-tolerant method to manage workloads with predictable or varying demand. Auto Scaling automatically adds instances during peak traffic and terminates them when demand is low, reducing compute cost while maintaining availability across multiple Availability Zones.

Reserved Instances (Option B) would force the company to pay for peak capacity all day, which is not cost-effective.

Stopping instances manually (Option C) or vertically scaling instances (Option D) reduces fault tolerance and increases operational overhead.

=====================================================

The recommended and simplest method for granting cross-account access to an S3 bucket is to use a bucket policy that grants permission to the other AWS account.

This provides direct, controlled, IAM-based access without duplication of data or use of distribution mechanisms like CloudFront.

Transfer Acceleration and replication are unrelated to permissions.

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AWS Global Accelerator is designed to improve the availability and performance of applications with global users by using the AWS global network. It provides static anycast IP addresses and routes user traffic over the AWS edge network to the optimal AWS Region and endpoint based on health, geography, and routing policies. Global Accelerator supports both TCP and UDP traffic and can have Network Load Balancers as endpoints.

For latency-sensitive workloads such as multiplayer gaming, Global Accelerator reduces latency and jitter compared to internet-based routing and handles Regional failover quickly.

CloudFront (Option A) is optimized for HTTP/HTTPS content caching and is not appropriate for arbitrary TCP/UDP gaming traffic. Application Load Balancers (Option B) do not support UDP traffic. API Gateway (Option D) is for HTTP APIs and is not suitable for raw TCP/UDP game traffic.

This design includes:

ALB: Supports AWS WAF integration.

Auto Scaling Group: Automatically scales based on load.

Multi-AZ Deployment: Increases resiliency and availability.

AWS WAF: Can be attached to ALB for application-layer protection.

“ALB is integrated with AWS WAF. You can deploy your EC2 instances in an Auto Scaling group across multiple Availability Zones to ensure high availability.”

— High Availability with Auto Scaling and ALB

Why not others?

A: Single AZ = not resilient

C: AWS WAF cannot attach to Route 53

D: NLB is not supported by AWS WAF

Cluster Placement Group: This type of placement group is designed to provide low-latency network performance and high throughput by grouping instances within a single Availability Zone. It is ideal for applications that require tightly coupled node-to-node communication.

Configuration:

When launching EC2 instances, specify the option to launch them in a cluster placement group.

This ensures that the instances are physically located close to each other, reducing latency and increasing network throughput.

Benefits:

Low-Latency Communication: Instances in a cluster placement group benefit from enhanced networking capabilities, enabling low-latency communication.

High Network Throughput: The network performance within a cluster placement group is optimized for high throughput, which is essential for HPC workloads.

Amazon Aurora PostgreSQL with Babelfish allows SQL Server applications to run directly on Aurora PostgreSQL with minimal code changes. Babelfish adds a SQL Server-compatible endpoint, significantly lowering costs compared to running licensed SQL Server instances on RDS or EC2.

AWS Documentation Extract:

“Babelfish for Aurora PostgreSQL enables Aurora to understand T-SQL and SQL Server wire protocol, allowing you to run SQL Server applications on Amazon Aurora PostgreSQL with lower costs.”

(Source: Babelfish for Aurora PostgreSQL documentation)

A, D: SQL Server on EC2 or RDS incurs high Microsoft licensing costs.

C: Plain PostgreSQL would require more code refactoring than Babelfish.

To securely publish messages to an encrypted Amazon SNS topic, the following steps are required:

A. Resource policy for SNS topic:Ensures that the Lambda function is explicitly allowed to publish messages to the topic.

C. Resource policy for KMS key:Provides the necessary permissions to use the customer-managed key for encryption.

F. Lambda execution role:Grants the Lambda function the necessary IAM permissions to use the encryption key.

Other options:

Bis invalid because using SSE-KMS does not eliminate the need for resource policies.

Doverlaps with A, but specifying the ARN in the topic policy is covered by creating the resource policy.

Eis unrelated as API Gateway is not required for this setup.

AWS Documentation Reference:

Amazon SNS and KMS Permissions

Using S3 event notifications to trigger AWS Lambda for file processing is a cost-effective and serverless solution. Lambda scales automatically with upload volume, and processing each file takes less than 5 seconds, fitting within Lambda's execution time.

Option A:AWS AppSync is designed for GraphQL APIs and is not suitable for file processing.

Option C:Kinesis is overkill and more expensive for this use case.

Option D:Running an EC2 instance incurs ongoing costs and is less flexible compared to Lambda.

AWS Documentation References:

Amazon S3 Event Notifications

AWS Lambda Overview

To handle increased loads effectively, it's essential to implement Auto Scaling for both frontend and backend tiers:

Frontend Auto Scaling Group: Scaling based on incoming network traffic ensures that the application can handle increased user requests.

Backend Auto Scaling Group: Scaling based on the Amazon SQS queue backlog ensures that the backend can process messages as they arrive, preventing delays.

This approach allows each tier to scale independently based on its specific load, ensuring optimal resource utilization and performance.

Amazon S3 Glacier Flexible Retrieval is a low-cost archival storage class that supports retrieval of data within minutes (expedited access ~1–5 minutes), making it ideal for audit scenarios where occasional, quick access to archived data is required. In contrast, Glacier Deep Archive takes hours to retrieve.

Amazon Macieis purpose-built for detecting PII in S3.

Option Auses EventBridge to filter SensitiveData findings and notify via SNS, meeting the requirements.

Options B and Dinvolve GuardDuty, which is not designed for PII detection.

Option Cuses SQS, which is less suitable for immediate notifications.

Storage Gateway Volume Gateway (Cached Volumes): This configuration allows you to store your primary data in Amazon S3 while retaining frequently accessed data locally in a cache for low-latency access.

Low-Latency Access: Frequently accessed data is cached locally on-premises, providing low-latency access while the less frequently accessed data is stored cost-effectively in Amazon S3.

Implementation:

Deploy a Storage Gateway appliance on-premises or in a virtual environment.

Configure it as a volume gateway with cached volumes.

Create volumes and configure your applications to use these volumes.

Minimal Infrastructure Changes: This solution integrates seamlessly with existing on-premises infrastructure, requiring minimal changes and reducing dependency on on-premises storage servers.

TooManyRequestsException errors occur when Lambda exceeds concurrency limits. The recommended pattern is to use Amazon SQS with Lambda to decouple and buffer traffic, ensuring that bursts of requests are queued and processed smoothly. Enabling provisioned concurrency for Lambda ensures that functions are pre-initialized and ready to handle spikes in load with low latency. Step Functions (B) is designed for workflow orchestration, not high-throughput request buffering. SNS with Lambda (C) does not provide buffering and may overwhelm Lambda during bursts. Reserved concurrency (D) limits function scaling instead of improving resilience. Therefore, option A provides a scalable and resilient solution, minimizing errors during traffic surges.

To allocate costs based on team ownership, AWS recommends tagging resources using cost allocation tags. Activating the “owner” tag as a cost allocation tag allows AWS Cost Explorer to categorize and group spending. Additionally, filtering for Amazon ECS services enables the visibility into service-specific usage. This approach is both scalable and operationally efficient.

Key Requirements:

Protect public endpoints (CloudFront distributions and ALBs) frommalicious attacks.

Centralizedmanagementacross multiple accounts in an organization.

Ability tomonitor security configurationseffectively.

Minimizeoperational overhead.

Analysis of Options

Option A:

AWS WAF:Protects web applications by filtering and blocking malicious requests. Rules can be applied to both ALBs and CloudFront distributions.

AWS Firewall Manager:Enables centralized management of WAF rules across multiple accounts in an AWS Organizations organization. It simplifies rule deployment, avoiding the need to configure rules individually in each account.

AWS Config:Monitors compliance by using rules that check Regional and global WAF configurations. Ensures that security configurations align with organizational policies.

Operational Overhead:Centralized management and automated monitoring reduce the operational burden.

Correct Approach:Meets all requirements with the least overhead.

Option B:

This approach involves applying WAF rules in each account manually.

While AWS Config and AWS Security Hub provide monitoring capabilities, managing individual WAF configurations in multiple accounts introduces significant operational overhead.

Incorrect Approach:Higher overhead compared to centralized management with AWS Firewall Manager.

Option C:

Similar to Option A but includesAmazon Inspector, which is not designed for monitoring WAF configurations.

AWS Security Hubis appropriate for monitoring but is redundant when Firewall Manager and Config are already in use.

Incorrect Approach:Adds unnecessary complexity and does not focus on monitoring WAF specifically.

Option D:

AWS Shield Advanced:Focuses on mitigating large-scale DDoS attacks but does not provide the fine-grained web application protection offered by WAF.

AWS Config:Can monitor Shield Advanced configurations but does not fulfill the WAF monitoring requirements.

Incorrect Approach:Does not address the need for WAF or centralized rule management.

Why Option A is Correct

Protection:

AWS WAF provides fine-grained filtering and protection against SQL injection, cross-site scripting, and other web vulnerabilities.

Rules can be applied at both ALBs and CloudFront distributions, covering all public endpoints.

Centralized Management:

AWS Firewall Manager enables security teams to centrally define and manage WAF rules across all accounts in the organization.

Monitoring:

AWS Config ensures compliance with WAF configurations by checking rules and generating alerts for misconfigurations.

Operational Overhead:

Centralized management via Firewall Manager and automated compliance monitoring via AWS Config greatly reduce manual effort.

AWS Solution Architect References

AWS WAF Documentation

AWS Firewall Manager Documentation

AWS Config Best Practices

AWS Organizations Documentation

Correct Approach:

AWS Security Groups:

Security groups operate at the instance level, making them the ideal tool for controlling access to specific resources such as an Amazon RDS database.

By default, security groups deny all incoming traffic. You can allow access by explicitly specifying another security group.

Associating an RDS database security group with the EC2 instances' security group ensures only the specified EC2 instances can access the RDS database.

Incorrect Options Analysis:

Option A: Using CIDR blocks for IP-based access is less secure and more difficult to manage. Additionally, Auto Scaling groups dynamically allocate IP addresses, making this approach impractical.

Option B: Network ACLs (NACLs) operate at the subnet level and are stateless. While NACLs can deny or allow traffic, they are not suited to application-specific access control.

Option D: Similar to Option B, using a NACL with CIDR ranges for EC2 IPs is difficult to manage and not application-specific.

AWS Shield Advanced provides:

Advanced DDoS detection and mitigation

24/7 access to the AWS DDoS Response Team (DRT)

Real-time metrics and alerts via CloudWatch

Integrated with CloudFront, ALB, Route 53, and Global Accelerator

“Shield Advanced provides enhanced detection and mitigation for more sophisticated DDoS attacks and gives you access to the AWS DDoS Response Team (DRT).”

— AWS Shield Advanced Overview

Incorrect Options:

A (AWS WAF): For application-layer filtering only.

B (Shield Standard): Basic protection, no DRT or attack visibility.

C (Macie): Used for discovering sensitive data in S3, unrelated to DDoS.

DynamoDB export to Amazon S3 (via point-in-time exports or table backups) “does not consume read capacity” and has no impact on table performance. Once data is in S3, Amazon Redshift can ingest efficiently with COPY from S3, which is the standard, parallel, high-throughput load path with minimal management. Direct COPY from DynamoDB (B) performs a table scan that can consume provisioned throughput, risking throttling. Building Lambda pipelines (C) adds custom code and scheduling overhead. Athena federated queries (D) are ad hoc analytics, not optimized for bulk, recurring warehouse loads. Therefore, exporting to S3 and loading with Redshift COPY maintains DynamoDB throughput and minimizes operational burden.

Amazon DynamoDB supports TTL (Time To Live) for automated, scheduled deletion of expired items. It also offers point-in-time recovery (PITR) to restore the table to any second within the retention window (typically up to 35 days), providing full data durability and protection. DynamoDB can efficiently handle frequent updates and offers predictable performance. MemoryDB is an in-memory store, not designed for durable recovery. S3 with lifecycle policies does not handle updates as efficiently for small, frequent writes and is not as optimal for session data.

Reference Extract:

"DynamoDB supports TTL for automated expiration and deletion of items and PITR for continuous backups and restoration of data."

Source: AWS Certified Solutions Architect – Official Study Guide, DynamoDB section.

Amazon RDSBlue/Green Deploymentsis the ideal solution for upgrading the database version with minimal operational overhead and no data loss. Blue/Green Deployments allows you to create a separate, fully managed "green" environment with the upgraded database version. You can test the new version in the green environment while the "blue" environment continuesserving production traffic. Once testing is complete, you can seamlessly switch traffic to the green environment without downtime.

This solution provides:

Fast, non-disruptive upgrade: Traffic is only switched to the new environment after testing, ensuring zero data loss.

Minimal operational overhead: AWS handles the infrastructure management, reducing manual intervention.

Option A (Manual snapshot): This requires manual intervention and involves more operational overhead.

Option B (Native backup/restore): This approach is more labor-intensive and slower than Blue/Green Deployments.

Option C (DMS): AWS DMS adds unnecessary complexity for a simple version upgrade when Blue/Green Deployments can handle the task more efficiently.

AWS References:

Amazon RDS Blue/Green Deployments

Amazon EFS provides a shared, fully managed, POSIX-compliant file system that can be mounted by all EC2 instances. Any update made to the file system is immediately visible to all instances, ensuring every new instance has the latest product manuals without delay.

EFS automatically scales storage and throughput, meeting high-demand conditions with no application changes required.

S3 requires instances to download files locally, causing delay and stale data issues (Options B and D). Instance store volumes (Option A) are ephemeral and not shared, making them unsuitable for consistent data distribution.

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To make the application highly available across regions:

Deploy the application in a different region using a newECS clusterandALBto ensure regional redundancy.

UseRoute 53 failover routingto automatically direct traffic to the healthy region in case of failure.

UseDynamoDB Global Tablesto ensure the database is replicated and available across multiple regions, supporting read and write operations in each region.

Option D (EKS cluster in the same region): This does not provide regional redundancy.

Option E (Global Secondary Indexes): GSIs improve query performance but do not provide multi-region availability.

Option F (PrivateLink): PrivateLink is for secure communication, not for cross-region high availability.

AWS References:

DynamoDB Global Tables

Amazon ECS with ALB

A. EventBridge rule:Triggers an event whenever there is a change in CloudFront distribution, ensuring real-time monitoring.

B. ALB with WAF:Focuses on application-level security, not CloudFront logging.

C. Lambda + SNS:Provides notifications upon detection of changes in logging configuration.

D. GuardDuty:Monitors anomalies but does not specifically address CloudFront logging changes.

E. Private API + WAF:Irrelevant to CloudFront logging changes.

AWS CloudFormationallows for the automated, repeatable setup of infrastructure, reducing human error and ensuring consistency.AWS Configprovides the ability to track changes in the infrastructure, ensuring that all changes are logged and auditable, which satisfies the requirement for tracking incremental changes.

Option A and C (AWS Organizations): AWS Organizations manage multiple accounts, but they are not designed for infrastructure setup or change tracking.

Option D (Service Catalog): Service Catalog is used for deploying products, not for setting up infrastructure or tracking changes.

AWS References:

AWS Config

AWS CloudFormation

AWS Well-Architected recommends multi-AZ, elastic architectures: use Auto Scaling groups across multiple Availability Zones for EC2 to eliminate single-AZ failure and automatically replace capacity. For relational databases, Amazon RDS Multi-AZ provides synchronous replication and automatic failover for high availability. Serving static content via Amazon CloudFront (with S3 origin) improves resiliency and performance by caching at edge locations and reducing origin load/latency. Options A and C concentrate compute in one AZ and lack resilient static delivery. Option D changes the stack unnecessarily and proposes EFS One Zone-IA for static assets, which is not multi-AZ and is intended for infrequently accessed, single-AZ workloads, reducing resilience. Therefore, B aligns with best practices for high availability, fault tolerance, and global performance.

Lambda@Edge allows you to run functions at CloudFront edge locations, enabling modifications to content before it's delivered to users, including compression — which directly reduces data transfer cost.

“Lambda@Edge can be used to compress or modify your content before delivering it to end users, which reduces the amount of data transferred.”

— Lambda@Edge Use Cases

Since code modifications aren’t allowed, using Lambda@Edge is a non-invasive way to:

Compress responses.

Reduce transfer size = lower CloudFront cost.

Incorrect Options:

B: S3 Transfer Acceleration improves speed, not cost.

C: Caching doesn’t help if content is always unique (single-use).

D: Multipart uploads help with large file uploads, not transfers.

AWS KMS with SSE-KMS provides granular key management and auditability. All use of KMS keys is logged in AWS CloudTrail, which allows compliance teams to monitor encryption and decryption operations. A bucket policy can be configured to enforce uploads only with the designated KMS key, ensuring that users cannot bypass encryption or change methods. Option A (SSE-S3 with bucket policy) enforces encryption but does not provide the same level of control or auditable key usage. Option C (client-side encryption) increases complexity and key management burden. Option D prevents bucket setting changes but does not prevent unencrypted uploads. Therefore, B ensures the most granular control, auditability, and compliance with financial data requirements.

Amazon Aurora PostgreSQL with Babelfish allows Aurora to understand SQL Server T-SQL and the SQL Server wire protocol. This enables applications to continue using SQL Server drivers, minimizing code changes (Option B).

Migration of schema and data is performed using AWS Schema Conversion Tool (SCT) and AWS Database Migration Service (DMS) (Option C), which is the AWS-recommended migration pattern for heterogeneous database migrations.

AWS DMS (Option E) does not rewrite application SQL.

RDS Proxy (Option D) does not translate SQL Server protocols.

Option A requires rewriting application queries, which contradicts the “minimal changes” requirement.

Using SQS as a buffer between S3 and the Lambda function ensures durability and allows for retries in case of processing failures. Messages in the queue can be retried by Lambda, and failed processing can be directed to a dead-letter queue for further inspection. This guarantees reliable and scalable message-driven processing.

Amazon SQS supports Interface VPC endpoints (AWS PrivateLink), enabling private connectivity from your VPC to SQS without using public IPs, traversing the public Internet, or requiring NAT/IGW. You can restrict access by attaching a queue resource policy that allows only the specific VPC endpoint and denies all other principals/paths, enforcing that all traffic stays on the AWS network. SSE-SQS (B) encrypts data at rest but does not influence network pathing. STS temporary credentials (C) handle authentication/authorization, not routing. VPC Flow Logs (D) are monitoring/visibility and do not prevent public egress. Creating an SQS VPC endpoint and tightening the queue policy satisfies the requirement of no public IP usage while maintaining secure, private access from serverless components in VPC subnets.

Option Auses an IAM role attached to the EC2 instance profile, enabling secure and automated access to Secrets Manager. This is the recommended approach.

Option Buses IAM users, which is less secure and harder to manage.

Option Cis not practical for accessing secrets programmatically.

Option Dviolates best practices by granting direct access to the EC2 instance.

This solution is the most cost-effective and scalable for analyzing large amounts of web traffic logs.

Amazon S3: Storing the logs in Amazon S3 is highly scalable, durable, and cost-effective. S3 is designed to handle large-scale data storage, which is ideal for storing tens of gigabytes of log data generated daily by multiple websites.

Amazon Athena: Athena is a serverless, interactive query service that allows you to analyze data in S3 using standard SQL. It works directly with the data stored in S3, so there’s no need to load the data into a database, which saves on costs and reduces complexity. Athena charges based on the amount of data scanned by queries, making it a cost-effective solution for on-demand analysis that only occurs once a week.

Why Not Other Options?:

Option B (Amazon RDS): Storing logs in a relational database like Amazon RDS would be more expensive due to the storage and I/O costs associated with RDS. Additionally, it would require more management overhead.

Option C (Amazon OpenSearch Service): OpenSearch is a good option for full-text search and analytics on log data, but it might be more costly and complex to manage compared to the simplicity and cost-effectiveness of Athena for periodic SQL-based queries.

Option D (Amazon EMR): While EMR can handle large-scale data processing, it involves more operational overhead and might be overkill for the type of ad-hoc, SQL-based analysis required here. Additionally, EMR costs can be higher due to the need to maintain a cluster.

AWS References:

Amazon S3- Information on how to store and manage data in Amazon S3.

Amazon Athena- Documentation on using Amazon Athena for querying data stored in S3 using SQL.

AWS Spot best practices recommend diversifying capacity across multiple instance types and Availability Zones and using the capacity-optimized (price-capacity-optimized) allocation strategy to choose pools with the deepest capacity for higher availability. Adding a small On-Demand base in the Auto Scaling group maintains steady, uninterrupted baseline processing while keeping costs low and absorbing Spot interruptions. Option C (lowest price) increases interruption risk. Capacity Reservations (B) target On-Demand capacity guarantees and add cost, not needed for Spot-based elasticity. Option E is redundant; diversification is already achieved with (D). This combination maximizes resiliency of Spot workloads while preserving strong cost efficiency and aligns with AWS guidance for fault-tolerant, stateless applications on Spot.

To enable DNS resolution from AWS VPCs to on-premises DNS servers over Direct Connect or VPN, AWS recommends using Amazon Route 53 Resolver with outbound endpoints. An outbound endpoint allows DNS queries originating in the VPC to be forwarded to a customer-managed DNS server (e.g., on-prem).

Next, a forwarding rule (Forward type) must be created to forward DNS queries for the custom domain internal.example.com to the on-premises DNS IP addresses. This rule defines what domain names are forwarded and to which DNS servers.

Finally, the rule must be associated with all workload VPCs to allow those VPCs to use the rule. There is no need to deploy endpoints in every VPC — one outbound endpoint is sufficient and can be shared across VPCs via rule association.

???? Reference:

Route 53 Resolver Endpoints

Best practices for hybrid DNS resolution

Amazon Macie: Detects sensitive data such as PII in S3 buckets using machine learning.

EventBridge Rule: Filters Macie findings for specific sensitive data events (e.g., SensitiveData).

SNS Notification: Provides real-time alerts to the security team for immediate action.

Amazon Macie Documentation,Amazon EventBridge Documentation

Service control policies (SCPs) in AWS Organizations apply to the accounts or OUs to which they are attached:

To restrict only nonproduction accounts, you can:

Attach the SCP directly to those specific member accounts (Option B), or

Create a dedicated OU for the nonproduction accounts and attach the SCP to that OU (Option E).

Both methods ensure that the deny policy affects only the nonproduction accounts and does not impact the production account.

Why the others are incorrect:

A: Attaching the SCP to the root OU would apply the deny to all accounts, including production, which does not meet the requirement.

C: SCPs attached to the management account only affect that account, not all member accounts.

D: Creating an OU for the production account and attaching the deny SCP there would block the prohibited instance types in production, which is the opposite of what is required.

AWS Systems Manager Session Manager allows secure, auditable SSH-like access to EC2 instances without the need to open SSH ports or manage bastion hosts. For this to work in a private subnet, an interface VPC endpoint is required (not a gateway endpoint).

The EC2 instances must have the AmazonSSMManagedInstanceCore policy attached to their IAM roles to allow Systems Manager operations.

With Session Manager, all session activity can be logged centrally to Amazon CloudWatch Logs or S3, satisfying the audit requirement and improving operational efficiency over manual SSH and bastion configurations.

Amazon RDS Performance Insights is a “database performance tuning and monitoring feature” that can be enabled with a few clicks and “helps you quickly assess the load on your database” and identify bottlenecks. It surfaces key metrics, including DB load, top SQL, waits, and host metrics such as CPU utilization, which are commonly used indicators for right-sizing (up or down). This provides the lowest operational effort compared to building log pipelines or querying CloudTrail (which does not capture SQL workload characteristics). AWS X-Ray traces application requests, not database internals, and CloudWatch Logs aggregation requires custom ingestion and analysis. Enabling Performance Insights directly on the RDS instance provides actionable utilization data to right-size with minimal setup.

The requirement is to provide granular, scalable access to thousands of tables and columns in a data lake across many users and departments, with the least operational overhead.

AWS Lake Formation supports tag-based access control (TBAC) using LF-tags (Lake Formation tags), which allows you to assign tags to tables, columns, and databases. You can then define permissions on resources by specifying tags rather than managing permissions for individual resources. This approach is highly scalable and efficient when dealing with a growing number of tables and columns. By associating IAM roles to departments and granting access based on LF-tags, you dramatically reduce the operational burden as new tables or columns are added; you only need to assign the appropriate tags.

Amazon Athena can directly query data in S3 with Lake Formation providing fine-grained access control.

AWS Documentation Extract:

"With LF-tag-based access control, you can grant permissions to resources based on tags, making it easy to manage access at scale, especially in environments with large and dynamic numbers of resources."

"LF-tags provide a scalable way to manage permissions for large numbers of resources without having to define permissions individually for each table or column."

(Source: AWS Lake Formation documentation, Access Control, Tag-Based Access Control)

Other options:

A: Would require managing explicit permissions for each table and column as the environment grows, increasing operational overhead.

B & D: Involve significant duplication of resources (clusters) and do not scale as efficiently as a centralized data lake with tag-based access.

The best practice for secure access control in AWS is to use IAM roles with least-privilege policies, granting only the permissions necessary to perform required tasks. Assigning roles individually ensures that developers cannot overstep their intended access boundaries.

Sharing credentials or using permanent access keys increases the risk of security breaches. Cognito is primarily intended for managing user access to applications, not AWS infrastructure. Thus, Option B best meets security and access control requirements.

AWS recommends using cost allocation tags to associate costs with owners (e.g., department, project) and AWS Budgets to create cost or usage budgets with alerts at defined thresholds (e.g., 60%). Budgets can send notifications via email or Amazon SNS when “Actual or forecasted” spend exceeds the threshold. Cost Explorer forecasts help visualize trends but do not provide budget alerting or ownership attribution by themselves. Trusted Advisor does not generate budget threshold alerts. Therefore, tagging resources for accountability and setting a budget with a 60% alert provides governance and proactive notifications aligned with cost control best practices for experimentation.

Amazon Athena provides a cost-effective, serverless way to query data without affecting the performance of DynamoDB. By using the Athena DynamoDB connector, the company can perform the necessary SQL queries without consuming read capacity on the DynamoDB table, which is essential for minimizing impact on provisioned throughput.

Key benefits:

Minimal Impact on Provisioned Capacity: Athena queries do not directly impact DynamoDB’s read capacity, making it ideal for running analytics without affecting the customer-facing workloads.

Cost-Effective: Athena is a serverless solution, meaning you pay only for the queries you run, making it highly cost-effective compared to running a dedicated cluster like Amazon EMR or Redshift.

AWS Documentation: The use of Athena to query DynamoDB through its connector aligns with AWS's best practices for performance efficiency and cost optimization​​.

AWS PrivateLinkis the most suitable solution for providing fine-grained access control while allowing multiple VPCs, potentially across multiple accounts, to access the new application. This approach offers the following advantages:

Fine-grained control: Endpoint policies can restrict access to specific services or principals.

No need for route table updates: Unlike VPC peering or transit gateways, AWS PrivateLink does not require complex route table management.

Scalable architecture: PrivateLink scales to support traffic from multiple VPCs.

Secure connectivity: Ensures private connectivity over the AWS network, without exposing resources to the internet.

Why Other Options Are Not Ideal:

Option A:

VPC peering is not scalable when connecting multiple VPCs or accounts.

Route table management becomes complex as the number of VPCs increases.Not scalable.

Option B:

While transit gateways provide scalable VPC connectivity, they are not ideal for fine-grained access control.

Transit gateways allow connectivity but do not inherently restrict access to specific applications.Not ideal for fine-grained access control.

Option D:

Exposing the application through an ALB over the internet is not secure and does not align with the requirement to use private network resources.Security risk.

AWS References:

AWS PrivateLink:AWS Documentation - PrivateLink

AWS Networking Services Comparison:AWS Whitepaper - Networking Services

Amazon Macie is a fully managed data security and data privacy service that uses machine learning and pattern matching to discover and protect sensitive data in AWS. To scale across Regions and accounts in AWS Organizations, Macie supports delegated administration, automated sensitive data discovery, and multi-account aggregation through a centralized admin account.

Amazon Aurora Serverless v2 provides cost-effective, on-demand, and auto-scaling database capacity. You pay only for actual usage, making it ideal for development and test environments that are not used continuously. It supports PostgreSQL and is suitable for variable and short-duration workloads, minimizing costs when databases are idle.

AWS Documentation Extract:

“Amazon Aurora Serverless v2 automatically adjusts database capacity based on application needs, ideal for development and test environments with intermittent usage.”

(Source: Aurora Serverless v2 documentation)

B: RDS instances run and accrue charges even when idle.

C, D: Aurora clusters/global databases are overkill and incur higher costs for dev/test.

Amazon RDS Proxy helps manage thousands of concurrent database connections by pooling and reusing them efficiently. It is especially useful for serverless applications like AWS Lambda that can open numerous connections quickly, potentially overwhelming the database. Using RDS Proxy reduces connection management overhead and improves fault tolerance.

IAM Access Analyzer analyzes permissions granted using policies to determine what resources are shared with an external entity, and helps identify excessive permissions or least privilege violations across all accounts in an AWS Organization. It is specifically designed for reviewing and refining IAM permissions with minimal administrative effort.

AWS Documentation Extract:

“IAM Access Analyzer helps you identify the resources in your organization and accounts, such as Amazon S3 buckets or IAM roles, that are shared with an external entity. You can also use Access Analyzer policy checks to refine permissions and implement least privilege.”

(Source: IAM Access Analyzer documentation)

A: Network Access Analyzer is for VPC network access analysis, not IAM permissions.

B: CloudWatch alarms are not suitable for detailed permission analysis.

D: Amazon Inspector is for security vulnerability assessment, not IAM policy review.

AWS best practice is to use IAM roles with instance profiles for EC2 instances so that applications obtain temporary credentials automatically and do not need to store access keys.

To honor the principle of least privilege, each microservice should have an IAM role that grants only the specific permissions it needs.

Therefore, creating individual IAM roles per microservice and attaching them via instance profiles (Option D) both minimizes long-term credential management and applies least privilege cleanly.

Why others are not correct:

A: Using IAM users with access keys in code is insecure and high-overhead (key rotation, secret management).

B: A single broad role violates least privilege because every microservice gets more permissions than it needs.

C: Separate accounts per microservice is extreme over-segmentation and significantly increases operational complexity.

AWS Fargate provides per-pod isolation for CPU, memory, storage, and networking, making it ideal for multi-tenant use cases.

AWS Documentation References:

EKS with Fargate

According to AWS best practices, each tier’s security group must restrict inbound traffic to only the upstream trusted source. For the web tier, the Application Load Balancer must be the only entity allowed to send traffic. AWS documentation specifies: “Restrict the security groups associated with your targets to accept traffic only from the load balancer.” This confirms that the web tier security group should allow inbound HTTPS from the ALB security group (A).

For communication between the web and application tiers, AWS states: “You can specify a security group as the source or destination in a rule” and “Create rules only for the protocols and ports required by your application.” Therefore, the application tier security group must allow inbound HTTPS traffic from the web tier security group (E).

For the database tier, AWS guidance says: “Allow only the necessary ports for database communication.” Microsoft SQL Server listens on port 1433 by default, so the database tier security group must allow inbound SQL Server traffic from the application tier security group (C).

Outbound rules (options B, D, and F) are unnecessary because AWS specifies that “Security groups are stateful. Return traffic is automatically allowed.” This means once inbound rules are defined, the return path is automatically permitted without extra outbound configurations.

This combination (A, C, E) applies the principle of least privilege, ensures end-to-end secure communication across tiers, and follows AWS recommendations for ALB-to-target security group setups.

CloudFront geographic restrictions (also known as geo-blocking) allow you to allow or deny content delivery to specific countries with minimal configuration.

“You can use geo restriction, also known as geoblocking, to prevent users in specific geographic locations from accessing content that you're distributing through a CloudFront web distribution.”

— CloudFront Geo Restriction

This is the most operationally efficient approach — no code, no signed URL logic.

Incorrect Options:

A/C: Signed URLs/cookies are for individual access control, not geo-blocking.

D: OAC controls access between CloudFront and S3, not to block specific countries.

Amazon RDS supports encryption at rest by using AWS KMS keys backed by AWS CloudHSM. This allows use of dedicated FIPS 140-2 Level 3 validated hardware modules to manage encryption keys, meeting compliance for sensitive data such as PII.

From AWS Documentation:

“You can use AWS KMS with keys that are backed by AWS CloudHSM to control the encryption of RDS databases. This provides dedicated HSM-backed key storage and management.”

(Source: Amazon RDS User Guide – Encrypting Amazon RDS Resources)

Why B is correct:

Meets the requirement for dedicated HSM hardware.

Fully integrates with RDS for transparent encryption at rest.

Satisfies compliance standards for healthcare and regulated data.

Why others are incorrect:

A: Keys in CloudHSM directly are not used by RDS; they must be managed through KMS integration.

C: EC2 instance stores are ephemeral, not suitable for RDS databases.

D: SSE-S3 applies to S3 objects, not databases.

To decouple distributed workloads and improve scalability and resiliency, Amazon SQS should be used as a reliable job queue. The compute nodes (workers) can poll the SQS queue for tasks, and EC2 Auto Scaling can dynamically scale instances based on the ApproximateNumberOfMessages metric.

From AWS Documentation:

“Amazon SQS enables you to decouple application components, allowing each part to scale independently. You can scale EC2 instances automatically based on the number of messages in the queue.”

(Source: Amazon SQS Developer Guide – Scaling Consumers with Auto Scaling)

Why B is correct:

Eliminates the single point of failure (the primary coordinator).

Enables event-driven scaling based on queue depth.

Provides durability and resiliency since messages are stored redundantly.

Fully managed and integrates seamlessly with Auto Scaling policies.

Why other options are incorrect:

A: Scheduled scaling does not respond to variable workloads.

C & D: Misuse of CloudTrail/EventBridge; not intended for workload coordination.

AWS Global Accelerator provides static anycast IP addresses that are announced from AWS edge locations. Traffic sent to these IPs is routed over the AWS global network to the nearest healthy endpoint (for example, an ALB or NLB) in any Region. Because clients connect to static IPs instead of DNS names that change, failover does not depend on DNS TTLs or client cache expiry, which avoids stale DNS entries.

You can register endpoints in multiple Regions and let Global Accelerator automatically fail over when health checks fail, all behind a single global endpoint.

CloudFront (Option A) is primarily for HTTP/HTTPS content caching and still uses DNS; it is not intended as a generic multi-Region failover solution for arbitrary applications.

Route 53 (Options B and D) relies on DNS; clients can cache DNS responses and may keep sending traffic to an unhealthy Region until TTLs expire, which does not meet the “avoid stale DNS client caches” requirement.

Background Jobs with Event Invocation Type:

The Event invocation type is asynchronous, meaning the Lambda function does not send an immediate result to the API Gateway and processes the request in the background. This is ideal for video encoding tasks that take time.

REST API vs. HTTP API:

REST APIs support advanced features like API keys, request validation, and throttling that HTTP APIs do not support fully.

Since the developer needs API keys and request validations, a REST API is the correct choice.

Integration with Lambda:

AWS Lambda integration is seamless with REST APIs, and using the Event invocation ensures asynchronous processing.

Incorrect Options Analysis:

Option A: HTTP API lacks full support for API keys and validation.

Option CandD: RequestResponse invocation type requires immediate responses, unsuitable for background jobs.

DynamoDB Streams: Captures real-time changes in DynamoDB tables and allows integration with Lambda for processing the changes.

Minimal Operational Overhead: Using a Lambda function directly to write data to S3 ensures simplicity and reduces the complexity of the pipeline.

Amazon DynamoDB Streams Documentation

HPC workloads require high-throughput, low-latency networking, especially for tightly-coupled applications like weather modeling, genomics, or real-time rendering.

A cluster placement group places instances in the same Availability Zone and on physically connected hardware, reducing network latency and increasing throughput.

Elastic Fabric Adapter (EFA) is a network device for EC2 instances that enables low-latency, high-throughput networking using OS-bypass technology, ideal for tightly-coupled HPC applications.

Each instance can support single-flow 10 Gbps bandwidth using EFA, and collectively, the cluster can achieve up to 100 Gbps aggregate throughput when properly configured.

This solution supports the Performance Efficiency and Resilience design principles and is a standard AWS-recommended pattern for HPC.

???? References:

EC2 Placement Groups

Elastic Fabric Adapter Overview

Best Practices for HPC on AWS

AWS recommends multi-Region active-active architectures for applications requiring high availability, automatic failover, and disaster recovery. Route 53 latency-based routing directs users to the Region providing the lowest latency and automatically shifts traffic if Regional endpoints become unhealthy.

Combined with Application Load Balancers and EC2-based microservices deployed in multiple Regions, this architecture delivers fault tolerance, multi-Region resiliency, and automatic recovery.

Option D provides high availability but does not inherently provide multi-Region failover routing without additional configuration. Option B is single-Region. Option A is not resilient.

=====================================================

AWS Lake Formation provides centralized data access control, including fine-grained (column-level) permissions for data stored in S3 and accessed through services like Amazon Athena.

Using a Lake Formation blueprint to ingest data from Aurora MySQL into the data lake keeps ingestion and governance integrated. When QuickSight uses Athena as the data source, Athena enforces Lake Formation’s column-level permissions automatically. This allows the marketing team to see only the authorized subset of columns without custom access-control logic.

Options A, B, and C rely on manually limiting columns at ingestion time or using IAM or S3 bucket policies, which do not provide true column-level authorization for SQL queries and require significantly more manual work and maintenance.

Protecting an application from layer 7 (application layer) DDoS attacks is best achieved by using AWS WAF (Web Application Firewall), which provides customizable protection against common web exploits including DDoS attacks at the application layer. AWS WAF supports managed rule groups maintained by AWS, which offer robust, tested protections against OWASP top 10 vulnerabilities and common attack patterns without requiring extensive manual rule creation.

While AWS Shield Standard provides basic network-layer DDoS protection automatically at no additional charge, it does not offer application-layer filtering capabilities. Therefore, option A alone is insufficient.

Option B, involving only custom rules, requires significant operational overhead and expertise, whereas AWS managed rules offer a turnkey solution with ongoing updates from AWS security teams.

Option D, using CloudFront in front of the ALB, can provide additional protection benefits such as caching and geographic restrictions, but the question specifically asks for protecting against layer 7 DDoS on the ALB directly. CloudFront plus WAF is a valid enhanced solution, but the direct and recommended answer in AWS official documents is to use AWS WAF managed rules directly with ALB for application-level protection.

By exporting AWS Cost and Usage Reports (CUR) to Amazon S3 and analyzing them with Amazon QuickSight, companies can generate interactive visual dashboards. This solution is fully AWS-managed, requires no third-party tools, and integrates deeply with AWS cost data.

Provisioned IOPS SSD (io1 or io2) volumes are designed to deliver predictable, high performance for I/O-intensive workloads such as databases. They offer consistent, low-latency performance and durability, making them ideal for business-critical applications that cannot tolerate latency or data loss.

EC2 Auto Scaling warm pools allow you to pre-initialize instances, reducing the delay in scale-out events. This results in significantly faster response times during demand surges while remaining cost-effective compared to always running at peak capacity.

AWS Transit Gateway is purpose-built for large-scale, hub-and-spoke network architectures. It simplifies connectivity between multiple VPCs and on-premises environments, which is ideal for managing hundreds of VPCs.

“AWS Transit Gateway enables you to connect your VPCs and on-premises networks through a central hub. This simplifies your network and puts an end to complex peering relationships.”

— Transit Gateway Documentation

Features:

Scales to thousands of VPCs.

Integrates with AWS Direct Connect via Direct Connect Gateway.

Centralized routing control.

Incorrect Options:

A: VPC endpoints are for private access to AWS services—not VPC-to-VPC connectivity.

C: Route 53 is DNS, not a network transport layer.

D: Secrets Manager is for secret storage, not networking.

To meet the requirement of controlling key rotation with minimal operational overhead, creating acustomer managed key(CMK) in AWS KMS is the optimal solution. With CMKs, you can define custom key rotation policies, ensuring that you retain control over the key lifecycle, including enabling automatic key rotation every year.

Key AWS features:

Custom Key Management: A customer managed key allows you to control the key policies, lifecycle, and enable key rotation for compliance.

Least Operational Overhead: Using a customer managed key simplifies encryption management while offering more flexibility than AWS managed or owned keys.

AWS Documentation: The AWS Well-Architected Framework recommends customer managed keys for environments where key control and flexibility are required​.

Partition Key Issue:

Using "service name" as the partition key results in uneven data distribution. Some shards may become hot due to excessive logs from certain services, leading to throttling errors.

Changing the partition key to "creation timestamp" ensures a more even distribution of records across shards.

Incorrect Options Analysis:

Option A: On-demand capacity mode eliminates throughput management but is more expensive and does not address the root cause.

Option B: Adding more shards does not solve the issue if the partition key still creates hot shards.

Option D: Using separate streams increases complexity and is unnecessary.

Amazon GuardDuty detects cryptocurrency mining and sends findings to Amazon EventBridge. You can use EventBridge to trigger an automated Lambda function to isolate EC2 instances (such as by removing security group access or stopping/isolating the instance).

AWS Documentation Extract:

"Amazon GuardDuty findings can be sent to Amazon EventBridge, which enables you to trigger an automated response using AWS Lambda."

(Source: AWS GuardDuty documentation)

B, C, D: Security Hub, Inspector, and Config are not directly used for this detection-to-isolation workflow.

AWS Global Accelerator: This service provides a global fixed entry point to your applications and optimizes the path to your application through the AWS global network, reducing latency and improving performance.

Accelerated TCP Connections:

Global Accelerator uses the AWS global network to route traffic to the nearest edge location, improving the performance and reliability of your live streams.

It provides static IP addresses that act as a fixed entry point to your application, simplifying DNS management.

High-Quality Streams:

By leveraging Global Accelerator, reporters can send live streams with the highest quality and low latency.

This service automatically reroutes traffic to the nearest available AWS Region, ensuring consistent performance even during traffic spikes or failures.

Operational Efficiency: Using Global Accelerator simplifies the network setup and provides an optimized path for live streams without the need for complex configurations, making it an efficient solution for real-time streaming applications.

AWS IAM Identity Center:

IAM Identity Centerprovides centralized access management for multiple AWS accounts within an organization and integrates seamlessly with existing identity providers (IdPs) throughSAML 2.0 federation.

It allows users to authenticate using their existing IdP credentials and gain access to AWS resources without the need to create and manage separate IAM users in each account.

IAM Identity Centeralso simplifies provisioning and de-provisioning users, as it can automatically synchronize users and groups from the external IdP to AWS, ensuring secure and managed access.

Integration with Existing IdP:

The solution involves configuringIAM Identity Centerto connect to the company's IdP using SAML. This setup allows employees to log in with their existing credentials, reducing the complexity of managing separate AWS credentials.

Once connected,IAM Identity Centerhandles authentication and authorization, granting users access to the AWS accounts based on their assigned roles and permissions.

Why the Other Options Are Incorrect:

Option A: Creating separateIAM usersfor each employee is not scalable or efficient. Managing thousands of IAM users across multiple AWS accounts introduces unnecessary complexity and operational overhead.

Option B: Using AWSroot userswith synchronized passwords is a security risk and goes against AWS best practices. Root accounts should never be used for day-to-day operations.

Option D:AWS Resource Access Manager (RAM)is used for sharing AWS resources between accounts, not for federating access for users across accounts. It doesn’t provide a solution for authentication via an external IdP.

AWS References:

AWS IAM Identity Center

SAML 2.0 Integration with AWS IAM Identity Center

By setting upIAM Identity Centerand connecting it to the existing IdP, the company can efficiently manage access for thousands of employees across multiple AWS accounts with a high degree of operational efficiency and security. Therefore,Option Cis the best solution.

AWS guidance is to cover steady baseline with commitments (Reserved Instances or Savings Plans) and use EC2 Spot Instances for burst capacity to minimize cost. Spot provides up to 90% discounts and is well-suited to fault-tolerant, queue-based workloads; interruptions are handled by replacing capacity automatically while messages remain durably in SQS. Using only Spot (A) risks capacity gaps; only RIs sized for peak (B) wastes cost during low demand. Option D scales on backlog but uses On-Demand for bursts, which is more expensive than Spot. With C, baseline capacity (RIs) keeps processing continuously (no downtime), and Spot adds cost-efficient throughput during spikes, aligning with Well-Architected cost and reliability patterns for queue workers.

The optimal solution for low-latency global caching with disaster recovery and cross-Region replication is to use Amazon ElastiCache Global Datastore for Redis OSS.

A Global Datastore enables fully managed cross-Region replication and supports automatic failover by promoting read replica clusters in another Region.

ElastiCache ensures encryption in-transit and at-rest, meeting compliance and security requirements.

It's a fully managed AWS-native feature, reducing operational effort compared to setting up DMS-based or snapshot-based replication manually.

Other options (A, C, D):

Require manual setup and management (e.g., custom DMS pipelines, snapshots).

Do not offer real-time replication or failover without manual intervention.

???? Reference:

ElastiCache Global Datastore for Redis

The best practice to securely provide short-term access to AWS resources, such as Amazon S3, without using long-term credentials, is to use AWS Security Token Service (STS). According to the AWS IAM Best Practices and the Security Pillar of the AWS Well-Architected Framework, temporary credentials should always be used over long-term credentials when possible.

From AWS IAM Documentation:

“Use temporary credentials (IAM roles and AWS STS) instead of long-term access keys. Temporary security credentials are short-term, automatically expire, and are retrieved using AWS STS.”

(Source: IAM Best Practices – IAM User Guide)

Option D outlines the use of a trust relationship and assume-role mechanism via AWS STS. This allows the on-premises application to request temporary, scoped-down credentials to upload files to S3 securely. This approach is:

Secure – Uses short-lived credentials with least privilege

Scalable – No need for EC2 or VPN tunnels

Low Operational Overhead – No infrastructure to maintain

AWS-Recommended – Aligned with security best practices

In contrast:

Option A uses long-term credentials, which is a security risk.

Option B requires additional infrastructure (EC2, VPN), increasing complexity and cost.

Option C relies on IP-based access, which is insecure and not a form of identity-based authentication.

To achieve high availability for the website, two key actions should be taken:

Amazon RDS for MySQL Multi-AZ: By migrating the database to an RDS for MySQL Multi-AZ deployment, the database becomes highly available. Multi-AZ provides automatic failover from the primary database to a standby replica in another Availability Zone, ensuring database availability even in the case of an AZ failure.

Application Load Balancer and Auto Scaling: Deploying an Application Load Balancer (ALB) in front of the EC2 instances ensures that traffic is evenly distributed across the instances. Configuring an Auto Scaling group to run EC2 instances across multiple Availability Zones ensures that the application remains available even if one instance or one AZ becomes unavailable. This setup enhances fault tolerance and improves reliability.

Why Not Other Options?:

Option A (Internet Gateway per AZ): Internet Gateways are region-wide resources and do not need to be provisioned per Availability Zone. This option does not contribute to high availability.

Option C (DynamoDB + Auto Scaling): DynamoDB would require changes to the application code to switch from MySQL, which is not possible per the question's constraints.

Option D (DataSync): AWS DataSync is used for data transfer and synchronization, not for achieving high availability for a database.

AWS References:

Amazon RDS Multi-AZ Deployments- Explanation of how Multi-AZ deployments work in Amazon RDS.

Application Load Balancing- Details on how to configure and use ALB for distributing traffic across multiple instances.

EC2 Account Attributes: Amazon EC2 allows you to set account attributes to automatically encrypt new EBS volumes. This ensures that all new volumes created in your account are encrypted by default.

Configuration Steps:

Go to the EC2 Dashboard.

Select "Account Attributes" and then "EBS encryption".

Enable default EBS encryption and select the default AWS KMS key or a customer-managed key.

Prevention of Unencrypted Volumes: By setting this account attribute, you ensure that it is not possible to create unencrypted EBS volumes, thereby enforcing compliance with security requirements.

Operational Efficiency: This solution requires minimal configuration changes and provides automatic enforcement of encryption policies, reducing operational overhead.

To analyze the performance of the web application with granularity of no more than 2 minutes, enablingdetailed monitoringon EC2 instances is the best solution. By default, CloudWatch provides metrics at a 5-minute interval. Enabling detailed monitoring allows you to collect metrics at 1-minute intervals, which will give you the level of granularity you need to analyze performance during peak traffic.

Amazon CloudWatch metrics can then be used to analyze CPU utilization, memory usage, disk I/O, and network throughput, among other performance-related metrics, at the desired granularity.

Option A: Sending CloudWatch logs to Redshift for analysis is unnecessary and overcomplicated for simple performance analysis, which can be done using CloudWatch metrics alone.

Option C: Fetching EC2 logs via Lambda adds complexity, and CloudWatch metrics already provide the required data for performance analysis.

Option D: Sending logs to S3 and using Redshift for analysis is also more complex than necessary for simple performance monitoring.

AWS References:

Monitoring Amazon EC2 with CloudWatch

Amazon CloudWatch Detailed Monitoring

AWS recommends Auto Scaling with dynamic scaling policies to handle unpredictable workload spikes. Target tracking scaling policies automatically adjust capacity based on defined metrics such as average CPU utilization or request count per target. This approach ensures applications maintain responsiveness without overprovisioning. Scheduled scaling (options B and C) is only effective when traffic patterns are predictable, which is not the case here. Reserved Instances or Spot Instances also do not address sudden demand changes effectively. Replacing the ALB with an NLB (D) does not solve latency caused by EC2 instance capacity. Therefore, using EC2 instances in an Auto Scaling group with a target tracking scaling policy is the most effective and cost-efficient solution for unpredictable, short-lived traffic spikes.

Key Requirements:

Host the frontend on AWS as a static website.

Protect the application from common web vulnerabilities.

Minimal operational overhead.

Analysis of Options:

Option A:

Hosting the frontend on EC2 with an ALB introduces unnecessary complexity for serving static content.

AWS WAF rules can protect the ALB, but managing EC2 instances adds operational overhead.

Incorrect Approach:High operational complexity for a simple static website.

Option B:

Amazon CloudFront:Acts as a global CDN, reducing latency and protecting against DDoS attacks.

Multiple Origins:Allows static content to be served from S3 while routing API traffic to the on-premises backend.

AWS WAF:Integrates with CloudFront to provide web application protection.

Correct Approach:Offers low operational overhead with optimal security and performance.

Option C:

Using NLB and Network Firewall is unnecessary for a static website. This approach increases cost and complexity without addressing the frontend requirements effectively.

Incorrect Approach:Over-engineered solution.

Option D:

Hosting the frontend on S3 and using API Gateway is a viable option, but managing AWS WAF rules separately for both the S3 bucket and the REST API increases complexity.

Incorrect Approach:Less efficient than using CloudFront with multiple origins.

AWS Solution Architect References:

Amazon CloudFront Overview

AWS WAF with CloudFront

The most secure solution for allowing EC2 instances to access an S3 bucket is by usingIAM roles. An IAM role can be created with an access policy that grants the required permissions (e.g., to read and write to the S3 bucket). The IAM role is then associated with the EC2 instances through anIAM instance profile.

By associating the role with the instances, the EC2 instances can securely assume the role and receive temporary credentials via the instance metadata service. This avoids the need to store credentials (such as access keys) on the instances or within the application, enhancing security and reducing the risk of credentials being exposed.

AWS CloudFormation can be used to automate the creation of the entire infrastructure, including EC2 instances, IAM roles, and associated policies.

AWS References:

IAM Roles for EC2 Instancesoutlines the use of IAM roles for secure access to AWS services.

AWS CloudFormation User Guidedetails how to create and manage resources using CloudFormation templates.

Why the other options are incorrect:

A. Save IAM access key in UserData: This is insecure because it involves storing long-term credentials in the instance user data, which can be exposed.

B. Store access keys in S3: This is also insecure, as it involves managing and distributing long-term credentials, which should be avoided.

D. Retrieve access keys via a script: This approach is unnecessarily complex and less secure than using IAM roles, which provide temporary credentials automatically.

TheAWS WAF Bot Control managed ruleis designed to automatically detect and mitigate bot traffic. This feature is particularly useful for addressing malicious traffic and conserving compute resources by filtering unnecessary requests at the ALB level.

Option A:Blocking IP addresses manually introduces significant operational overhead and is not scalable against dynamic, worldwide malicious traffic.

Option C:AWS Shield provides DDoS protection, but the scenario does not describe a DDoS attack. WAF is better suited for managing application-layer threats like bot traffic.

Option D:The AWS WAF IP reputation rule helps block traffic from known bad IPs but may not address bot traffic effectively.

AWS Documentation References:

AWS WAF Bot Control

AWS WAF Managed Rules

Amazon Managed Service for Apache Flink (formerly Kinesis Data Analytics) is a fully managed, serverless service for real-time processing of streaming data. You can consume data from Kinesis Data Streams, perform anomaly detection, and then output the results to another Kinesis stream. This approach is loosely coupled, fully managed, and does not require modifying the application code.

AWS Documentation Extract:

“Amazon Managed Service for Apache Flink enables you to process streaming data in real time, integrating with Kinesis Data Streams as source and sink, and is fully managed and serverless.”

(Source: Apache Flink on AWS documentation)

B: S3/Redshift is not real-time and adds complexity.

C, D: EC2/ECS solutions are not serverless or fully managed.

AWS Storage Gateway file gateway presents a file interface backed by Amazon S3 and supports NFS. This allows local applications to access data via NFS while also enabling cloud applications to use the data stored in S3 for analytics and processing, fulfilling both hybrid and cloud-native requirements.

Reference Extract:

"AWS Storage Gateway file gateway offers NFS and SMB access to data stored in Amazon S3, supporting hybrid workloads for local and cloud access."

Source: AWS Certified Solutions Architect – Official Study Guide, Hybrid and Storage Gateway section.

CloudTrail log file validation ensures that the log files have not been altered or deleted after delivery, providing an immutable audit log. Using KMS-managed encryption keys for CloudTrail log files adds another layer of data security, and AWS Config can monitor compliance to ensure this security is always enforced.

Reference Extract:

"CloudTrail log file validation provides assurance about the integrity of CloudTrail logs. Using SSE-KMS encryption and monitoring with AWS Config helps secure and audit logs for compliance."

Source: AWS Certified Solutions Architect – Official Study Guide, CloudTrail Security section.

For applications requiring high network throughput and low latency between EC2 instances, AWS recommends using a Cluster Placement Group:

Cluster Placement Group: Packs instances close together inside an Availability Zone, enabling workloads to achieve the low-latency network performance necessary for tightly-coupled node-to-node communication.

Enhanced Networking: Selecting instance types that support enhanced networking provides higher bandwidth, higher packet-per-second (PPS) performance, and consistently lower inter-instance latencies.

By combining a Cluster Placement Group with enhanced networking-enabled instance types, the company can meet the stringent performance requirements of its real-time industrial application.

Amazon SQS is a fully managed message queuing service that reliably decouples and scales microservices, distributed systems, and serverless applications. By using SQS, microservices can communicate asynchronously, handle bursts of traffic, and avoid data loss by buffering messages until they are processed. Deploying the services on ECS with AWS Fargate further reduces operational overhead by removing the need to manage servers, allowing independent scaling of each microservice.

Reference Extract:

"Amazon SQS decouples application components and enables message durability and scaling. AWS Fargate removes the need to manage infrastructure, supporting independent scaling and minimal operational overhead."

Source: AWS Certified Solutions Architect – Official Study Guide, Microservices and Messaging section.

Amazon RDS for MySQL Reserved Instances provide significant savings over on-demand pricing when you plan to run the database for long periods. This is the most cost-effective option for non-production, long-running managed MySQL workloads.

Reference Extract:

"Reserved Instances provide a significant discount compared to On-Demand pricing and are recommended for steady-state workloads that run for an extended period."

Source: AWS Certified Solutions Architect – Official Study Guide, RDS Cost Optimization section.

For short, frequent daily spikes (15–20 minutes), the most cost-effective scaling behavior typically comes from target tracking scaling driven by a request-based metric, because it continuously adjusts capacity to maintain a chosen target value rather than adding/removing capacity in coarse steps. Option D uses a custom CloudWatch metric representing the number of GET requests (sourced from ALB access logs, application instrumentation, or request counting logic) and applies target tracking so the Auto Scaling group scales out and in proportionally to demand. This helps avoid both under-provisioning (bad performance during spikes) and over-provisioning (wasted cost between spikes), which is exactly what cost-optimized elasticity aims for.

Option A (simple scaling) is usually less cost-efficient for bursty traffic because it relies on fixed adjustments and alarm thresholds, often with cooldowns. With 15–20 minute spikes, simple scaling can react too slowly, overshoot, or oscillate, leaving extra instances running after the spike or failing to ramp fast enough at the start. Option B (predictive scaling) is intended for regular, forecastable demand patterns, but it’s not always the most cost-effective choice for repeated short spikes because it can pre-scale conservatively and may require more historical data and tuning; it is often paired with dynamic scaling anyway. Option C uses UnhealthyHostCount, which is a health signal—not a demand signal—and scaling on unhealthy hosts can increase cost without addressing request volume; it may also mask underlying application issues rather than scaling to meet load.

Because the requirement explicitly allows standard or custom metrics and focuses on scaling based on request volume, D best matches a cost-efficient, responsive approach that directly tracks incoming workload.

Amazon ECS on AWS Fargate: AWS Fargate is a serverless compute engine for containers that works with Amazon ECS. It allows you to run containers without managing servers or clusters.

Amazon EFS: Amazon Elastic File System (EFS) provides a simple, scalable, fully managed elastic NFS file system for use with AWS Cloud services and on-premises resources. It can be mounted to ECS tasks running on Fargate, allowing containers to access a shared file system with standard file system semantics, including OS-level permissions.

Edge-Optimized API: Designed for global users by routing requests through CloudFront's edge locations, reducing latency.

Content Encoding: Enabling content encoding compresses data, further optimizing performance by decreasing payload size.

Caching: Adding API Gateway caching reduces the number of calls to Lambda and database backends, improving latency.

Reserved Concurrency: Although useful, this does not directly affect latency for transferring static and dynamic content.

AWS API Gateway Edge-Optimized APIs Documentation

This architecture uses ALB for routing, Auto Scaling for elasticity, SQS to buffer unprocessed orders and decouple services, and RDS Multi-AZ for high availability and durability of transactional data. This ensures resilience and fault tolerance even during traffic spikes.

Option Bensures the use of S3 Object Lock and Versioning to meet compliance for immutability. CloudFront enhances performance while a bucket policy ensures secure access.

Option Alacks immutability safeguards.

Option Cintroduces unnecessary complexity.

Option Dmisses out on additional security benefits offered by CloudFront.

This solution offers the most scalable and cost-effective approach with minimal changes to the existing web portal and no code modifications.

Amazon EC2 On-Demand Instances in an Auto Scaling Group: Running the web portal on EC2 On-Demand instances ensures 100% uptime and scalability. The Auto Scaling group will maintain the desired number of instances, automatically scaling up or down as needed, ensuring high availability for the employee web portal.

AWS Lambda for Document Extraction: Lambda is a serverless compute service that allows you to run code in response to events without provisioning or managing servers. By using Lambda to run the document extraction program, you can trigger the function whenever an employee uploads a document. This approach is cost-effective since you only pay for the compute time used by the Lambda function.

No Code Changes Required: This solution integrates with the existing infrastructure with minimal implementation effort and does not require any modifications to the web portal's code.

Why Not Other Options?:

Option B (Spot Instances): Spot Instances are not suitable for workloads requiring 100% uptime, as they can be terminated by AWS with short notice.

Option C (Savings Plan): A Savings Plan could reduce costs but does not address the requirement for running the document extraction program efficiently or without code changes.

Option D (S3 with API Gateway and Lambda): This would require significant changes to the existing web portal setup, including moving the portal to S3 and reconfiguring its architecture, which contradicts the requirement of minimal implementation effort and no code changes.

AWS References:

Amazon EC2 Auto Scaling- Information on how to use Auto Scaling for EC2 instances.

AWS Lambda- Overview of AWS Lambda and its use cases.

AWS Transit Gateway simplifies network connectivity by acting as a hub that can connect VPCs and on-premises networks through VPN or Direct Connect. It provides scalability and reduces administrative overhead by eliminating the need to manage complex peering relationships as the number of accounts and VPCs grows.

Big data workloads that need to process terabytes of data in memory requirememory-optimized instancesfor the core and task nodes to ensure sufficient memory for processing data efficiently.

Primary Node:Ageneral purpose instanceis suitable because it manages cluster operations, including coordination and monitoring, and does not process data directly.

Core and Task Nodes:These nodes handle data storage and processing.Memory-optimized instancesare ideal because they provide high memory-to-CPU ratios, which is critical for in-memory big data workloads.

Why Other Options Are Incorrect:

Option A:Storage optimized and compute optimized instances are not suitable for workloads that rely heavily on in-memory processing.

Option B:A memory-optimized primary node is unnecessary because the primary node does not process data.

Option D:General purpose instances for all nodes will not provide sufficient memory for processing terabytes of data in memory.

AWS Documentation References:

Amazon EMR Instance Types

Memory-Optimized Instances

For a MySQL database experiencing high write operations, using Amazon RDS with Provisioned IOPS (io1 or io2) SSD storage is recommended to achieve consistent and low-latency performance. Provisioned IOPS allows you to specify a desired IOPS rate, which is crucial for write-intensive workloads.

Monitoring write operation metrics through Amazon CloudWatch enables you to observe performance and adjust the provisioned IOPS as needed to meet application demands.

Amazon SQS is the AWS-recommended service for handling decoupled, scalable, ordered, durable message ingestion with potentially large workloads. It supports payloads up to 256 KB directly and up to several MB using S3-backed large-payload extensions.

Lambda functions can process messages from SQS with automatic scaling. ECS with the Fargate launch type provides a serverless container platform for the frontend, scaling based on demand without managing servers.

SNS (Options B and D) is not a queue, does not provide durable message buffering, and is not appropriate for variable, bursty workloads that may exceed backend throughput. Lambda@Edge (Options A and D) is unsuitable for backend order processing because it runs at CloudFront edge locations with strict limitations.

CloudFront Signed Cookies:

CloudFront signed cookies allow the company to provide access to premium users while maintaining a single, consistent URL.

This approach is simpler and more scalable than managing presigned URLs for each file.

Incorrect Options Analysis:

Option A: Using EC2 and EBS increases complexity and cost.

Option B: Managing presigned URLs for each file is not scalable.

Option D: CloudFront signed URLs require unique URLs for each file, which does not meet the requirement for a single URL.

AWS Step Functions provides a low-code, fully managed workflow service with a visual interface to orchestrate AWS Glue jobs in sequence. Step Functions integrates natively with AWS Glue and can be triggered by Amazon EventBridge based on events or schedules.

AWS Documentation Extract:

“AWS Step Functions makes it easy to coordinate multiple AWS services into serverless workflows so you can build and update apps quickly. Step Functions provides visual workflows and integrates with AWS Glue for ETL orchestration.”

(Source: AWS Step Functions documentation)

A: Manual scripting and dashboards do not provide a low-code or integrated visual workflow.

C: QuickSight is for BI, not workflow visualization.

D: ECS adds unnecessary complexity.

Amazon FSx for NetApp ONTAP supports Multi-AZ, providing automatic failover between Availability Zones for high availability. It exposes ONTAP LUNs over the iSCSI protocol, delivering shared block storage semantics with low latency and consistent performance to EC2 clients across AZs. This meets the requirement for “highly available” and “low-latency” block access across multiple AZs. S3/S3 File Gateway (A) is object/file, not block storage. EBS (B, D) provides block storage to a single instance in a single AZ; EBS volumes cannot be shared across instances/AZs, and host-side sync scripts add latency, complexity, and do not provide true HA. FSx for ONTAP natively provides synchronous HA pair replication, fast failover, and supports iSCSI multipathing for resilient, performant access suited to latency-sensitive trading workloads.

The Amazon CloudWatch agent is required to collect memory utilization metrics (as memory metrics are not reported by default). A target tracking policy is the simplest and most effective way to scale based on a custom metric such as mem_used_percent.

Reference Extract:

"Install the CloudWatch agent to collect memory metrics, and create a target tracking scaling policy using these custom metrics."

Source: AWS Certified Solutions Architect – Official Study Guide, Monitoring and Scaling section.

A. Fixed desired instances:Does not adapt to traffic load fluctuations, leading to inefficiencies.

B. Larger EC2 instances:Increases costs unnecessarily.

C. Target tracking scaling policy:Adjusts capacity based on actual demand, optimizing costs.

D. Instance store volumes:Not persistent and unsuitable for shared data across instances.

Enabling Multi-AZ deployment for an Amazon RDS DB instance is the simplest and most effective way to improve database availability and eliminate a single point of failure. Multi-AZ deployments provide automatic failover to a standby instance in case of a failure of the primary instance. This approach is managed by AWS and only requires a modification to the existing instance, with minimal manual intervention or downtime, thus providing the least implementation effort.

Reference Extract from AWS Documentation / Study Guide:

"With Multi-AZ deployments, Amazon RDS automatically creates a primary DB Instance and synchronously replicates the data to a standby instance in a different Availability Zone (AZ). In case of a failure of the primary DB Instance, Amazon RDS automatically fails over to the standby so that database operations can resume quickly."

Source: AWS Certified Solutions Architect – Official Study Guide, RDS High Availability section.

AWS Control Tower: Provides a managed service to set up and govern a secure, multi-account AWS environment based on AWS best practices. It automates the setup of AWS Organizations and applies security controls (guardrails).

Networking Account:

Create a centralized networking account that includes a VPC with both private and public subnets.

This centralized VPC will manage and control the networking resources.

AWS Resource Access Manager (AWS RAM):

Use AWS RAM to share the subnets from the networking account with the other workload accounts.

This allows different workload accounts to utilize the shared networking resources without the need to manage their own VPCs.

Operational Efficiency: Using AWS Control Tower simplifies the setup and governance of multiple AWS accounts, while AWS RAM facilitates centralized management of networking resources, reducing operational overhead and ensuring consistent security and compliance.

UsingAD ConnectorwithAWS IAM Identity Center(formerly AWS Single Sign-On) allows the company to leverage its existingon-premises Active Directoryfor centralized identity management and access control. AD Connector acts as a proxy to the on-premises AD withoutrequiring additional infrastructure or complex setup. This solution integrates seamlessly with AWS, allowing the development team to use their existing AD credentials to access AWS resources across multiple accounts managed by AWS Organizations. The permissions for AWS resources can be managed centrally through IAM Identity Center by configuring permission sets.

This solution provides:

Least operational overhead: AD Connector is fully managed, and IAM Identity Center allows centralized management of permissions across accounts.

Secure access: The solution complies with security policies by using existing AD authentication mechanisms.

Option A (AWS Managed AD): Setting up a fully managed AWS AD and establishing a trust is more complex and involves additional operational overhead.

Option B (IAM Users): Manually managing IAM users and permissions is less scalable and increases operational complexity.

Option D (Cognito): Amazon Cognito is more suited for user-facing applications rather than internal identity management for AWS resources.

AWS References:

AD Connector with IAM Identity Center

AWS IAM Identity Center