RedHat EX200 Red Hat Certified System Administrator -RHCSA Exam Practice Test

groupadd adminuser

useradd natasha -G adminuser

useradd haryy -G adminuser

useradd sarah -s /sbin/nologin

Passwd user name // to modify password or echo redhat | passwd --stdin user name id natasha // to view user group.

yum install vsftpd

/etc/init.d/vsftpd start

chkconfig vsftpd on

/proc is the virtual filesystem, containing the information about the running kernel.

To change the parameter of running kernel you should modify on /proc. From Next reboot the system, kernel will take the value from /etc/sysctl.conf.

nameserver is specified in question,

1. Vi /etc/resolv.conf

nameserver 192.168.0.254

2. host server1.example.com

yum -y install sssd authconfig-gtk krb5-workstation authconfig-gtk // open the graphical interface

Modify user account database to ldap, fill up DN and LDAP SERVER as questions required, use TLS to encrypt connections making tick, write http://server.domain11.example.com/pub/EXAMPLE-CA-CERT to download ca, authentication method choose ldap password.

You can test if the ldapuser is added by the following command:

Id ldapuser1

Note: user password doesn’t not need to set

Configure the client:

Yum -y install chrony

Vim /etc/chrony.conf

Add: server classroom.example.com iburst

Start: systemctl enable chronyd

systemctl restart chronyd

Validate: timedatectl status

Using the browser open the URL in the question, download kernel file to root or home directory.

uname –r// check the current kernel version

rpm –ivh kernel-*.rpm

vi /boot/grub.conf// check

Some questions are: Install and upgrade the kernel as required. To ensure that grub2 is the default item for startup.

Yum repo : http://content.example.com/rhel7.0/x86-64/errata

OR

uname -r // check kernel

Yum-config-manager --add-repo=“http://content.example.com/rhel7.0/x86-64/ errata”

Yum clean all

Yum list kernel// install directly

Yum -y install kernel// stuck with it, do not pipe! Please do not pipe!

Default enable new kernel grub2-editenv list// check

Modify grub2-set-default “kernel full name”

Grub2-mkconfig –o/boot/grub2/grub.cfg// Refresh

*

[root@node1 ~]# mkdir -p /mnt/shares

[root@node1 ~]# ls -lrt /mnt/

[root@node1 ~]# chgrp sharegrp /mnt/shares/

[root@node1 ~]# chmod 2770 /mnt/shares/

[root@node1 ~]# ls -lrt /mnt/

### For Checking ###

[root@node1 ~]# su - harry

[harry@node1 ~]$ cd /mnt/shares/

[harry@node1 shares]$ touch harry

[harry@node1 shares]$ logout

[root@node1 ~]# su - natasha

[natasha@node1 ~]$ cd /mnt/shares/

[natasha@node1 shares]$ touch natasha

[natasha@node1 shares]$ ls -lrt

-rw-rw-r--. 1 harry sharegrp 0 Mar 21 06:03 harry

-rw-rw-r--. 1 natasha sharegrp 0 Mar 21 06:03 natasha

• vim /etc/sysctl.conf net.ipv4.ip_forward = 1

• sysctl –w (takes effect immediately)

If no “sysctl.conf” option, use these commands:

• sysctl –a |grep net.ipv4
• sysctl –P net.ipv4.ip_forward = 1
• sysctl -w

# yum install -y httpd

# chkconfig httpd on

# cd /var/www/html

# wget http://ip/dir/example.html

# cp example.com index.html

# vim /etc/httpd/conf/httpd.conf

NameVirtualHost 192.168.0.254:80

DocumentRoot /var/www/html/

ServerName station.domain40.example.com

• First check the size of Logical Volume: lvdisplay /dev/vo/myvol
• Make sure that the filesystem is in a consistent state before reducing:

# fsck -f /dev/vo/myvol

• Now reduce the filesystem by 200MB.

# resize2fs /dev/vo/myvol 200M

• It is now possible to reduce the logical volume. #lvreduce /dev/vo/myvol -L 200M

• Verify the Size of Logical Volume: lvdisplay /dev/vo/myvol
• Verify that the size comes in online or not: df -h

• Create a partition having size 5 GB and change the syste id '8e'.
• use partprobe command
• pvcreate /dev/hda9 Suppose your partition number is hda9.
• vgextend test0 /dev/hda9 vgextend command add the physical disk on volume group.
• lvextend -L+5120M /dev/test0/lvtestvolume
• verify using lvdisplay /dev/test0/lvtestvolume.

(1)find /etc -size 10k -exec cp {} /tmp/findfiles \;

(2)find / -user lucy -exec cp -a {} /tmp/findfiles \;

Note: If find users and permissions, you need to use cp - a options, to keep file permissions and user attributes etc.

• echo "1" >/proc/sys/net/ipv4/ip_forward
• vi /etc/sysctl.conf

net.ipv4.ip_forward = 1

If you want to use the Linux System as a Router to make communication between different networks, you need enable the IP forwarding. To enable on running session just set value 1 to

/proc/sys/net/ipv4/ip_forward. As well as automatically turn on the IP forwarding features on next boot set on /etc/sysctl.conf file.

• useradd eric
• passwd eric
• vi /etc/passwd
• eric:x:505:505::/home/eric:/sbin/nologin

Which shell or program should start at login time is specified in /etc/passwd file? By default, Redhat Enterprise Linux assigns the /bin/bash shell to the users. To deny the interactive login, you should write /sbin/nologin or /bin/ false instead of login shell.

mkdir/root/findfiles

find / -user jack -exec cp -a {} /root/findfiles/ \; ls /root/findresults

Download the new kernel file and then install it.

[root@desktop8 Desktop]# ls

kernel-2.6.32-71.7.1.el6.x86_64.rpm

kernel-firmware-2.6.32-71.7.1.el6.noarch.rpm

[root@desktop8 Desktop]# rpm -ivh kernel-*

Preparing... ###########################################

[100%]

1:kernel-firmware

########################################### [ 50%]

2:kernel

########################################### [100%]

Verify the grub.conf file, whether use the new kernel as the default boot. [root@desktop8 Desktop]# cat /boot/grub/grub.conf default=0

title Red Hat Enterprise Linux Server (2.6.32-71.7.1.el6.x86_64)

root (hd0,0)

kernel /vmlinuz-2.6.32-71.7.1.el6.x86_64 ro root=/dev/mapper/vol0-root rd_LVM_LV=vol0/root rd_NO_LUKS rd_NO_MD

rd_NO_DM LANG=en_US.UTF-8 SYSFONT=latarcyrheb-sun16 KEYBOARDTYPE=pc KEYTABLE=us crashkernel=auto rhgb quiet

initrd /initramfs-2.6.32-71.7.1.el6.x86_64.img

• if=/dev/zero of=/swapfile bs=1M count=600 mkswap /swapfile

/etc/fstab:

/swapfile swap swap defaults 0 0 mount -a

*

[root@node2 ~]# lsblk

NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT

vdd 252:48 0 5G 0 disk

vde 252:64 0 10G 0 disk

[root@node2 ~]# yum install kmod-kvdo vdo

[root@node2 ~]# systemctl enable --now vdo

[root@node2 ~]# systemctl start vdo

[root@node2 ~]# systemctl status vdo

[root@node2 ~]# vdo create --name=vdo1 --device=/dev/vde --vdoLogicalSize=50G

[root@node2 ~]# vdostats --hu

Device Size Used Available Use% Space saving%

/dev/mapper/vdo1 10.0G 4.0G 6.0G 40% N/A

[root@node2 ~]# mkfs.xfs -K /dev/mapper/vdo1

*

[root@node2 ~]# lsblk

NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT

vde 252:64 0 10G 0 disk

└─vdo1 253:4 0 50G 0 vdo

[root@node2 ~]# mkdir /vbread

[root@node2 ~]# blkid

/dev/mapper/vdo1: UUID="1ec7a341-6051-4aed-8a2c-4d2d61833227" BLOCK_SIZE="4096" TYPE="xfs"

[root@node2 ~]# vim /etc/fstab

UUID=1ec7a341-6051-4aed-8a2c-4d2d61833227 /vbread xfs defaults,x-systemd.requires=vdo.service 0 0

[root@node2 ~]# mount /dev/mapper/vdo1 /vbread/

[root@node2 ~]# df -hT

Filesystem Type Size Used Avail Use% Mounted on

/dev/mapper/vdo1 xfs 50G 390M 50G 1% /vbread

fdisk -cu /dev/vda// in the way of expanding the partition, don’t make main partition

partx –a /dev/vda

mkswap /dev/vdax

swapon /dev/vdax

swapon –s

vi /etc/fstab

/dev/vdaxswapswapdefaults0 0

mount -a