Preparation Set 2

Q1:Break into serverA and then set the root password to root. Set the target as multi-user and make sure it boots into that automatically. Reboot to confirm.

 
# Select the Rescue Mode by up down arrows , and press e 
# Add the following line at the end of the text 'quiet'
rd.break
# Press ctrl+x
# Follow the commands
switch_root:/# mount -o remount,rw /sysroot
switch_root:/# chroot /sysroot
sh-5.1# passwd
sh-5.1# touch /.autorelabel
sh-5.1# systemctl set-default multi-user
sh-5.1# systemctl get-default
sh-5.1# exit
switch_root:/# reboot

Q2 : Configure Hostname and Ip Address on this machine

IP Address : 192.168.208.138

NetMask : 255.255.255.0

Gateway : 192.168.208.2

DNS : 192.168.208.2

 
[root@serverA ~]# nmcli conn add con-name serverAnet2 ifname ens160 type ethernet ipv4.method manual ipv4.addresses 192.168.208.138/24 ipv4.dns 192.168.208.2 ipv4.gateway 192.168.208.2
Connection 'serverAnet2' (db86b64e-9645-4888-9a40-34d0a6256327) successfully added.
 
[root@serverA ~]# nmcli conn show
NAME                UUID                                  TYPE      DEVICE
serverAnet          62012638-3b99-4f06-9501-1387844d33a5  ethernet  ens160
lo                  f1ffff9a-fa27-4b6a-b791-1a5bb234841d  loopback  lo
serverAnet2         db86b64e-9645-4888-9a40-34d0a6256327  ethernet  --
Wired connection 1  4569ab1e-41c7-4a01-bb5b-d02ad68c5d8b  ethernet  --
 
[root@serverA ~]# nmcli conn up serverAnet2
Connection successfully activated (D-Bus active path: /org/freedesktop/NetworkManager/ActiveConnection/3)
[root@serverA ~]# cat /etc/NetworkManager/system-connections/serverAnet2.nmconnection
[connection]
id=serverAnet2
uuid=db86b64e-9645-4888-9a40-34d0a6256327
type=ethernet
interface-name=ens160
 
[ethernet]
 
[ipv4]
address1=192.168.208.138/24,192.168.208.2
dns=192.168.208.2;
method=manual
 
[ipv6]
addr-gen-mode=default
method=auto
 
[proxy]

Q3: Enable ssh access for root on both servers.

 
# Configuration file of ssh
[root@serverA ~]# vim /etc/ssh/sshd_config 
PermitRootLogin yes
# Restart the sshd service
[root@serverA ~]# systemctl restart sshd
 
#SERVER A
[root@serverA ~]# ssh-keygen
Generating public/private rsa key pair.
Enter file in which to save the key (/root/.ssh/id_rsa):
Enter passphrase (empty for no passphrase):
Enter same passphrase again:
Your identification has been saved in /root/.ssh/id_rsa
Your public key has been saved in /root/.ssh/id_rsa.pub
The key fingerprint is:
SHA256:bZchcrO7nh452I8+I299R0Prtog3KhdrZHO+s+tYJCI root@serverA
The key's randomart image is:
+---[RSA 3072]----+
|                 |
|                 |
|        . + .    |
|         + + o . |
|       ES.+.o.. .|
|        .+.Oo. o.|
|        . O.*....|
|        ..+@==oo.|
|         B%*=BBo.|
+----[SHA256]-----+
[root@serverA ~]# ssh-copy-id root@192.168.208.137
/usr/bin/ssh-copy-id: INFO: Source of key(s) to be installed: "/root/.ssh/id_rsa.pub"
/usr/bin/ssh-copy-id: INFO: attempting to log in with the new key(s), to filter out any that are already installed
/usr/bin/ssh-copy-id: INFO: 1 key(s) remain to be installed -- if you are prompted now it is to install the new keys
root@192.168.208.137's password:
 
Number of key(s) added: 1
 
Now try logging into the machine, with:   "ssh 'root@192.168.208.137'"
and check to make sure that only the key(s) you wanted were added.
 
[root@serverA ~]# ssh root@192.168.208.137
Activate the web console with: systemctl enable --now cockpit.socket
Last login: Tue Oct  8 14:28:52 2024 from 192.168.208.138

Q4: Configure min length of password to be 8

 
[root@serverA ~]# vim /etc/security/pwquality.conf
[root@serverA ~]# grep minlen /etc/security/pwquality.conf
 minlen = 8

Q5: Create a script to add new group from a list

 
[root@serverA scripts]# cat grouplist.txt
dba_admin:5010
dba_managers:5011
dba_staff:5012
dba_intern:5013
it_staff:5014
it_managers:5015
[root@serverA scripts]# cat creategroup.sh
for i in $(cat ./grouplist.txt)
do
	groupname=$(echo $i | cut -f 1 -d :)
	groupid=$(echo $i | cut -f 2 -d :)
	groupadd -g $groupid $groupname
	echo "group created : $groupname:$groupid "
done

Q6:Create a script to delete two last groups from /etc/group

 
[root@serverA scripts]# cat groupdel.sh
for i in $(tail -2 /etc/group)
do
	groupname=$(echo $i | cut -f 1 -d :)
	groupdel $groupname
	echo "Deleted $groupname"
done

Q7: Secure copy all the script files to server B

 
[root@serverA ~]# scp scripts/* root@192.168.208.137:/root/
creategroup.sh                                                                             100%  195   424.6KB/s   00:00
groupdel.sh                                                                                100%  127   394.3KB/s   00:00
grouplist.txt                                                                              100%   95   242.4KB/s   00:00
script1.sh                                                                                 100%  189   486.0KB/s   00:00
script2.sh                                                                                 100%  144   437.8KB/s   00:00
student.sh                                                                                 100%  228   786.9KB/s   00:00
userlist.txt                                                                               100%  166   519.0KB/s   00:00
 
[root@serverB ~]# ls
creategroup.sh  groupdel.sh  grouplist.txt  script1.sh  script2.sh  student.sh  userlist.txt

Q8: Change password for nancy mike harry natasha user1 using script

 
[root@serverA scripts]# cat changepassword.sh
num=0
for i in nancy mike harry natasha user1
do
	echo $i
	echo "redhat" | passwd --stdin $i
done

Q9: Define Command Alias

 
# Temporary alias to view last ten log messages 
[root@serverA log]# alias logive='tail -10 /var/log/messages'
[root@serverA log]# logive
Oct  9 13:49:00 serverA chronyd[942]: System clock wrong by 1.454455 seconds
Oct  9 13:49:42 serverA systemd[1]: Starting PackageKit Daemon...
Oct  9 13:49:42 serverA systemd[1]: Started PackageKit Daemon.
Oct  9 13:50:05 serverA chronyd[942]: System clock wrong by 1.291550 seconds
Oct  9 13:51:10 serverA chronyd[942]: System clock wrong by 1.703638 seconds
Oct  9 13:52:14 serverA chronyd[942]: System clock wrong by 1.964906 seconds
Oct  9 13:53:19 serverA chronyd[942]: System clock wrong by 1.901705 seconds
Oct  9 13:54:24 serverA chronyd[942]: System clock wrong by 1.837731 seconds
Oct  9 13:55:29 serverA chronyd[942]: System clock wrong by 1.761417 seconds
Oct  9 13:56:34 serverA chronyd[942]: System clock wrong by 1.209373 seconds
 
# Permanent alias to clear screen using safagara
[root@serverA ~]# vim .bashrc
[root@serverA ~]# tail -1 .bashrc
alias safagara='clear'
[root@serverA ~]# source .bashrc
[root@serverA ~]# safagara

Q10: On server1 create a tar w/gzip archive of /etc called etc_archive.tar.gz in the /archives directory.

 
[root@serverA archives]# tar -zcvf /archives/etc_archive.tar.gz /etc

Q11: On server1 create a star w/bzip2 archive of /usr/share/doc called doc_archive.tar.bz2 in the /archives directory.

 
[root@serverA archives]# tar -jcvf /archives/doc_archive.tar.bz2  /usr/share/doc

Q12: On server1 create a folder called /links, and under links create a file called file01. Create a soft link called file02 pointing to file01, and a hard link called file03 pointing to file01. Check your work.

 
[root@serverA links]# vim file01
[root@serverA links]# ln -s file01 file02
[root@serverA links]# ln file01 file03
[root@serverA links]# ls -lai
total 12
270703 drwxr-xr-x.  2 root root   48 Oct  9 14:59 .
   128 dr-xr-xr-x. 22 root root 4096 Oct  9 14:53 ..
320748 -rw-r--r--.  2 root root   15 Oct  9 14:59 file01
320749 lrwxrwxrwx.  1 root root    6 Oct  9 14:59 file02 -> file01
320748 -rw-r--r--.  2 root root   15 Oct  9 14:59 file03

Q13: Find all setuid files on server1 and save the list to /root/suid.txt.

 
[root@serverA /]# find / -type f -perm -u+s >/root/suid.txt
find: ‘/proc/6193/task/6193/fdinfo/5’: No such file or directory
find: ‘/proc/6193/fdinfo/6’: No such file or directory
[root@serverA /]# cat /root/suid.txt
/usr/bin/chage
/usr/bin/gpasswd
/usr/bin/newgrp
/usr/bin/fusermount3
/usr/bin/mount
/usr/bin/umount
/usr/bin/fusermount
/usr/bin/pkexec
/usr/bin/su
/usr/bin/crontab
/usr/bin/sudo
/usr/bin/chfn
/usr/bin/vmware-user-suid-wrapper
/usr/bin/passwd
/usr/bin/chsh
/usr/bin/at
/usr/sbin/pam_timestamp_check
/usr/sbin/unix_chkpwd
/usr/sbin/grub2-set-bootflag
/usr/sbin/userhelper
/usr/sbin/mount.nfs
/usr/lib/polkit-1/polkit-agent-helper-1
/usr/libexec/sssd/krb5_child
/usr/libexec/sssd/ldap_child
/usr/libexec/sssd/proxy_child
/usr/libexec/sssd/selinux_child
/usr/libexec/dbus-1/dbus-daemon-launch-helper
/usr/libexec/Xorg.wrap
/usr/libexec/cockpit-session

Q14: Find all files larger than 3MB in the /etc directory on server1 and copy them to /largrfiles.

 
[root@serverA /]# find /etc -type f -size +3M -exec cp -rf {} /largrfiles/ \;
[root@serverA /]# ls
afs          bin   dev  exams  home        lib    loans  mnt  proc    root  sbin  sys  usr
autorelabel  boot  etc  found  largrfiles  lib64  media  opt  remote  run   srv   tmp  var
 
[root@serverA largrfiles]# ls -lh
total 16M
-r--r--r--. 1 root root  13M Oct  9 15:07 hwdb.bin
-rw-r--r--. 1 root root 3.5M Oct  9 15:07 policy.33

Q15: Persistently mount /export/dba_files from the server 192.168.55.47 under /mnt/dba_files.

 
[root@serverA mnt]# showmount -e 192.168.208.137
Export list for 192.168.208.137:
/export/dba_files            192.168.208.138
 
[root@serverA mnt]# vim /etc/fstab
[root@serverA mnt]# tail -1 /etc/fstab
192.168.208.137:/export/dba_files	/mnt/dba_files		nfs	defaults	0	0
 
[root@serverA mnt]# systemctl daemon-reload
[root@serverA mnt]# mount -a
[root@serverA mnt]# ls
dba_files  hgfs  wshare

Q16: Create a job using at to write "This task was easy!" to /exams/at_job.txt in 10 minutes.

 
[root@serverA exams]# rpm -q at
at-3.1.23-11.el9.aarch64
[root@serverA exams]# systemctl status atd
 
[root@serverA exams]# at now + 10 minutes
warning: commands will be executed using /bin/sh
at> echo "This task was easy!" >/exams/at_job.tx
at> <EOT>
job 1 at Wed Oct  9 16:37:00 2024

Q17: Create a job using cron to write "Wow! I'm going to pass this test!" every Tuesday at 3pm to /var/log/messages.

 
[root@serverA ~]# rpm -q cronie
cronie-1.5.7-11.el9.aarch64
[root@serverA ~]# systemctl status crond.service
 
[root@serverA ~]# crontab -e
 
[root@serverA ~]# crontab -l
00	15	*	*	2	echo "Wow! I'm going to pass this test!">>/var/log/messages

Q18: Write a script named awesome.sh in the root directory on server1.

a) If “me” is given as an argument, then the script should output “Yes, I’m awesome.”
b) If “them” is given as an argument, then the script should output “Okay, they are awesome.”
c) If the argument is empty or anything else is given, the script should output “Usage ./awesome.sh me|them”

 
[root@serverA ~]# touch awesome.sh
[root@serverA ~]# chmod u+x awesome.sh
[root@serverA ~]# ls -lh awesome.sh
-rwxr--r--. 1 root root 0 Oct  9 16:41 awesome.sh
 
[root@serverA ~]# cat awesome.sh
 
if [ $1 == "me" ]
then
	echo " Yes, I’m awesome."
elif [ $1 == "you" ]
then
	echo "Okay, they are awesome."
else
	echo "Usage ./awesome.sh me|them"
fi
 
[root@serverA ~]# vim awesome.sh
[root@serverA ~]# ./awesome.sh me
 Yes, I’m awesome.
[root@serverA ~]# ./awesome.sh you
“Okay, they are awesome.”
[root@serverA ~]# ./awesome.sh they
Usage ./awesome.sh me|them

Put SELinux on server2 in permissive mode.

 
# Temporary
[root@serverA ~]# setenforce 0
[root@serverA ~]# getenforce
Permissive
 
# Permanent
[root@serverA ~]# vim /etc/selinux/config
SELINIUX=permissive

Modify the bootloader with the following parameters:

Increase the timeout using GRUB_TIMEOUT=10
Add the following line: GRUB_TIMEOUT_STYLE=hidden
Add quiet to the end of the GRUB_CMDLINE_LINUX line
Set grub password

 
[root@serverA default]# pwd
/etc/default
[root@serverA default]# ls
grub  useradd
[root@serverA default]# vim grub
GRUB_TIMEOUT=10
GRUB_TIMEOUT_STYLE=hidden
GRUB_CMDLINE_LINUX 
 
[root@serverA default]# grub2-mkconfig -o /boot/grub2/grub.cfg
Generating grub configuration file ...
Adding boot menu entry for UEFI Firmware Settings ...
done
 
[root@serverA grub2]# grub2-setpassword
Enter password:
Confirm password:
# user.cfg file is generated
[root@serverA grub2]# ls
fonts  grub.cfg  grubenv  user.cfg
 
[root@serverA grub2]# grub2-mkconfig -o /boot/grub2/grub.cfg
Generating grub configuration file ...
Adding boot menu entry for UEFI Firmware Settings ...
done

Q19: Configure NTP synchronization on serverA. Point them to us.pool.ntp.org.

 
[root@serverA ~]# rpm -q chrony
chrony-4.6-1.el9.aarch64
[root@serverA ~]# systemctl status chrony
 
[root@serverA ~]# vim /etc/chrony.conf
server us.pool.ntp.org iburst
 
[root@serverA ~]# systemctl restart chronyd
 
[root@serverA ~]# timedatectl set-ntp true
 
[root@serverA ~]# chronyc sources
MS Name/IP address         Stratum Poll Reach LastRx Last sample
===============================================================================
^? 5-243-119-74.ritternet.c>     0   7     0     -     +0ns[   +0ns] +/-    0ns

Q20: On serverB, create a new 2GiB volume group on /dev/nvme0n2 named "platforms_vg".

 
# Creating PV
[root@serverB ~]# pvcreate /dev/nvme0n2
  Physical volume "/dev/nvme0n2" successfully created.
 
[root@serverB ~]# pvs
  PV             VG Fmt  Attr PSize  PFree
  /dev/nvme0n1p3 cs lvm2 a--  18.41g    0
  /dev/nvme0n2      lvm2 ---   5.00g 5.00g
 
[root@serverB ~]# pvdisplay /dev/nvme0n2
  "/dev/nvme0n2" is a new physical volume of "5.00 GiB"
  --- NEW Physical volume ---
  PV Name               /dev/nvme0n2
  VG Name
  PV Size               5.00 GiB
  Allocatable           NO
  PE Size               0
  Total PE              0
  Free PE               0
  Allocated PE          0
  PV UUID               w2w0QG-KmiP-PFLH-i7ug-lFhE-GT03-pGWMMV
 
# Creating VG
[root@serverB ~]# vgcreate platforms_vg /dev/nvme0n2
  Volume group "platforms_vg" successfully created
[root@serverB ~]# vgs
  VG           #PV #LV #SN Attr   VSize  VFree
  cs             1   2   0 wz--n- 18.41g     0
  platforms_vg   1   0   0 wz--n- <5.00g <5.00g
[root@serverB ~]# vgdisplay platforms_vg
  --- Volume group ---
  VG Name               platforms_vg
  System ID
  Format                lvm2
  Metadata Areas        1
  Metadata Sequence No  1
  VG Access             read/write
  VG Status             resizable
  MAX LV                0
  Cur LV                0
  Open LV               0
  Max PV                0
  Cur PV                1
  Act PV                1
  VG Size               <5.00 GiB
  PE Size               4.00 MiB
  Total PE              1279
  Alloc PE / Size       0 / 0
  Free  PE / Size       1279 / <5.00 GiB
  VG UUID               h5BI36-oqCW-GysU-F6BW-iWGG-EY1k-sf2a74

Q21: Under the "platforms_vg" volume group, create a 500MiB logical volume name "platforms_lv" and format it as ext4.

 
[root@serverB ~]# lvcreate -L 500M --name platforms_lv  /dev/platforms_vg
  Logical volume "platforms_lv" created.
 
[root@serverB ~]# lvs
  LV           VG           Attr       LSize   Pool Origin Data%  Meta%  Move Log Cpy%Sync Convert
  root         cs           -wi-ao----  16.41g
  swap         cs           -wi-ao----   2.00g
  platforms_lv platforms_vg -wi-a----- 500.00m
 
[root@serverB ~]# mkfs -t ext4 /dev/platforms_vg/platforms_lv
mke2fs 1.46.5 (30-Dec-2021)
Creating filesystem with 512000 1k blocks and 128016 inodes
Filesystem UUID: 7b622c82-cbdb-42c6-b96b-78b036b3bc1b
Superblock backups stored on blocks:
	8193, 24577, 40961, 57345, 73729, 204801, 221185, 401409
Allocating group tables: done
Writing inode tables: done
Creating journal (8192 blocks): done
Writing superblocks and filesystem accounting information: done
 
[root@serverB ~]# blkid /dev/platforms_vg/platforms_lv
/dev/platforms_vg/platforms_lv: UUID="7b622c82-cbdb-42c6-b96b-78b036b3bc1b" TYPE="ext4"
 
[root@serverB ~]# lvdisplay /dev/platforms_vg/platforms_lv
  --- Logical volume ---
  LV Path                /dev/platforms_vg/platforms_lv
  LV Name                platforms_lv
  VG Name                platforms_vg
  LV UUID                32KpXC-96VG-zjPX-Mu0n-vIOj-8l98-0neu8g
  LV Write Access        read/write
  LV Creation host, time serverB, 2024-10-10 06:25:00 +0545
  LV Status              available
  # open                 0
  LV Size                500.00 MiB
  Current LE             125
  Segments               1
  Allocation             inherit
  Read ahead sectors     auto
  - currently set to     256
  Block device           253:2

Q22: Mount it persistently under /mnt/platforms_lv.

 
[root@serverB ~]# vim /etc/fstab
/dev/platforms_vg/platforms_lv	/mnt/platforms_lv	ext4	defaults	0	0
 
[root@serverB ~]# systemctl daemon-reload
[root@serverB ~]# mount -a
[root@serverB ~]# lsblk
NAME                        MAJ:MIN RM  SIZE RO TYPE MOUNTPOINTS
nvme0n2                     259:4    0    5G  0 disk
└─platforms_vg-platforms_lv 253:2    0  500M  0 lvm  /mnt/platforms_lv

Q23: Extend the "platforms_lv" volume and partition by 500MiB.

 
[root@serverB ~]# lvextend -L +500M /dev/platforms_vg/platforms_lv
  Size of logical volume platforms_vg/platforms_lv changed from 500.00 MiB (125 extents) to 1000.00 MiB (250 extents).
  Logical volume platforms_vg/platforms_lv successfully resized.
 
[root@serverB ~]# resize2fs /dev/platforms_vg/platforms_lv

Q24: On serverB, create a 500MiB swap partition on /dev/nvme0n3 and mount it persistently.

 
# Create a new partition 
[root@serverB ~]# gdisk /dev/nvme0n3
Command (? for help): n
Partition number (1-128, default 1):
First sector (34-4194270, default = 2048) or {+-}size{KMGTP}:
Last sector (2048-4194270, default = 4194270) or {+-}size{KMGTP}: +500M
Current type is 8300 (Linux filesystem)
Hex code or GUID (L to show codes, Enter = 8300): 8200
Changed type of partition to 'Linux swap'
 
Command (? for help): p
Number  Start (sector)    End (sector)  Size       Code  Name
   1            2048         1026047   500.0 MiB   8200  Linux swap
 
Command (? for help): w
Do you want to proceed? (Y/N): y
OK; writing new GUID partition table (GPT) to /dev/nvme0n3.
The operation has completed successfully.
 
[root@serverB ~]# lsblk
NAME                        MAJ:MIN RM  SIZE RO TYPE MOUNTPOINTS
...
nvme0n3                     259:5    0    2G  0 disk
└─nvme0n3p1                 259:7    0  500M  0 part
 
[root@serverB ~]# mkswap /dev/nvme0n3p1
Setting up swapspace version 1, size = 500 MiB (524283904 bytes)
no label, UUID=a11734f4-084d-4260-8880-477c5fb68967
 
[root@serverB ~]# vim /etc/fstab
/dev/nvme0n3p1		swap		swap	defaults	0	0
[root@serverB ~]# systemctl daemon-reload
[root@serverB ~]# swapon -a
 
[root@serverB ~]# swapon /dev/nvme0n3p1
[root@serverB ~]# lsblk
NAME                        MAJ:MIN RM  SIZE RO TYPE MOUNTPOINTS
...
nvme0n3                     259:5    0    2G  0 disk
└─nvme0n3p1                 259:7    0  500M  0 part [SWAP]
 
[root@serverB ~]# free -h
               total        used        free      shared  buff/cache   available
Mem:           3.5Gi       1.9Gi       696Mi        30Mi       1.1Gi       1.6Gi
Swap:          2.5Gi       0.0Ki       2.5Gi

Q25: On serverB, using the remaining space on /dev/nvme0n3, create a volume group with the name networks_vg.

 
[root@serverB ~]# gdisk /dev/nvme0n3
Command (? for help): p
Number  Start (sector)    End (sector)  Size       Code  Name
   1            2048         1026047   500.0 MiB   8200  Linux swap
 
Command (? for help): n
Partition number (2-128, default 2):
First sector (34-4194270, default = 1026048) or {+-}size{KMGTP}:
Last sector (1026048-4194270, default = 4194270) or {+-}size{KMGTP}:
Current type is 8300 (Linux filesystem)
Hex code or GUID (L to show codes, Enter = 8300): 8e00
Changed type of partition to 'Linux LVM'
 
Command (? for help): p
Number  Start (sector)    End (sector)  Size       Code  Name
   1            2048         1026047   500.0 MiB   8200  Linux swap
   2         1026048         4194270   1.5 GiB     8E00  Linux LVM
 
Command (? for help): w
Do you want to proceed? (Y/N): y
The operation has completed successfully.
 
[root@serverB ~]# partprobe /dev/nvme0n3
 
[root@serverB /]# vgcreate -s 8M network_vg /dev/nvme0n3p2
  Volume group "network_vg" successfully created
[root@serverB /]# vgs
  VG           #PV #LV #SN Attr   VSize  VFree
  cs             1   2   0 wz--n- 18.41g     0
  network_vg     1   0   0 wz--n- <1.51g <1.51g
  platforms_vg   1   1   0 wz--n- <5.00g <4.02g
[root@serverB /]# vgdisplay network_vg
  --- Volume group ---
  VG Name               network_vg
  System ID
  Format                lvm2
  Metadata Areas        1
  Metadata Sequence No  1
  VG Access             read/write
  VG Status             resizable
  MAX LV                0
  Cur LV                0
  Open LV               0
  Max PV                0
  Cur PV                1
  Act PV                1
  VG Size               <1.51 GiB
  PE Size               8.00 MiB
  Total PE              193
  Alloc PE / Size       0 / 0
  Free  PE / Size       193 / <1.51 GiB
  VG UUID               DtodYM-SUu8-P1VA-JzQg-KXwx-r0zp-Fnlkka

Q26: Under the "networks_vg" volume group, create a logical volume with the name networks_lv. Ensure it uses 8 MiB extents. Configure the volume to use 75 extents. Format it with the vfat file system and ensure it mounts persistently on /mnt/networks_lv.

 
[root@serverB /]# lvcreate -l 75 --name network_lv /dev/network_vg
  Logical volume "network_lv" created.
[root@serverB /]# lvs
  LV           VG           Attr       LSize    Pool Origin Data%  Meta%  Move Log Cpy%Sync Convert
  root         cs           -wi-ao----   16.41g
  swap         cs           -wi-ao----    2.00g
  network_lv   network_vg   -wi-a-----  600.00m
  platforms_lv platforms_vg -wi-ao---- 1000.00m
[root@serverB /]# lvdisplay /dev/network_vg/network_lv
  --- Logical volume ---
  LV Path                /dev/network_vg/network_lv
  LV Name                network_lv
  VG Name                network_vg
  LV UUID                dYeE1B-b1qx-dZ6M-BUfH-ZREx-MppZ-DWZoUw
  LV Write Access        read/write
  LV Creation host, time serverB, 2024-10-10 07:05:55 +0545
  LV Status              available
  # open                 0
  LV Size                600.00 MiB
  Current LE             75
  Segments               1
  Allocation             inherit
  Read ahead sectors     auto
  - currently set to     256
  Block device           253:3
 
[root@serverB /]# mkfs -t vfat /dev/network_vg/network_lv
mkfs.fat 4.2 (2021-01-31)
[root@serverB /]# blkid /dev/network_vg/network_lv
/dev/network_vg/network_lv: UUID="C393-F585" TYPE="vfat"
 
[root@serverB ~]# vim /etc/fstab
[root@serverB ~]# tail -1 /etc/fstab
/dev/network_vg/network_lv	/mnt/network_lv		vfat	defaults	0	0
 
[root@serverB ~]# systemctl daemon-reload
[root@serverB ~]# mount -a
[root@serverB ~]#  lsblk
NAME                        MAJ:MIN RM  SIZE RO TYPE MOUNTPOINTS
...
└─nvme0n3p2                 259:7    0  1.5G  0 part
  └─network_vg-network_lv   253:3    0  600M  0 lvm  /mnt/network_lv

Q27: On server2, create a 5TB thin-provisioned volume on /dev/nvme0n4 called "thin_vol" backed by a pool called "thin_pool" on a 4.5GB volume group called "thin_vg". Format it as xfs and mount it persistently under /mnt/thin_vol.

Thin LV (thin_vol) on a thin pool (thin_pool)

pv
vg
lv - thin pool - lvcreate --type thin-pool -L|--size Size[m|UNIT] VG / lvcreate --type thin-pool -L 4.5G --name thin_pool /dev/thin_vg
lv - thin lv - lvcreate -V|--virtualsize Size[m|UNIT] --thinpool LV VG / lvcreate -V 5T --thinpool thin_pool /dev/thin_vg

 
 
# Step 1 : Create PV thin_vg 4.5GB
[root@serverA ~]# pvcreate /dev/nvme0n4
  WARNING: adding device /dev/nvme0n4 with idname eui.c01979bdec673bd0000c296e16438846 which is already used for missing device.
  Physical volume "/dev/nvme0n4" successfully created.
[root@serverA ~]# pvs
  PV             VG     Fmt  Attr PSize  PFree
  /dev/nvme0n1p3 cs     lvm2 a--  18.41g    0
  /dev/nvme0n3   wgroup lvm2 a--   5.99g 3.99g
  /dev/nvme0n4          lvm2 ---   5.00g 5.00g
 
# Step 2: Create VG
[root@serverA ~]# vgcreate thin_vg /dev/nvme0n4
  WARNING: adding device /dev/nvme0n4 with idname eui.c01979bdec673bd0000c296e16438846 which is already used for missing device.
  Volume group "thin_vg" successfully created
[root@serverA ~]# vgs
  VG      #PV #LV #SN Attr   VSize  VFree
  cs        1   2   0 wz--n- 18.41g     0
  thin_vg   1   0   0 wz--n- <5.00g <5.00g
  wgroup    1   1   0 wz--n-  5.99g  3.99g
 
# Step 3 : Create a thin pool -  lvcreate --type thin-pool -L|--size Size[m|UNIT] VG 
[root@serverA ~]# lvcreate --type thin-pool -L 4.5G --name thin_pool thin_vg
  Thin pool volume with chunk size 64.00 KiB can address at most <15.88 TiB of data.
  Logical volume "thin_pool" created.
[root@serverA ~]# lvs
  LV        VG      Attr       LSize  Pool Origin Data%  Meta%  Move Log Cpy%Sync Convert
  root      cs      -wi-ao---- 16.41g
  swap      cs      -wi-ao----  2.00g
  thin_pool thin_vg twi-a-tz--  4.50g             0.00   10.60
  wshare    wgroup  -wi-ao----  2.00g
 
# Step 4: Create a thin LV in a thin pool - lvcreate -V|--virtualsize Size[m|UNIT] --thinpool LV VG
[root@serverA ~]# lvcreate -V 5T --name thin_vol --thinpool thin_pool thin_vg
  WARNING: Sum of all thin volume sizes (5.00 TiB) exceeds the size of thin pool thin_vg/thin_pool and the size of whole volume group (<5.00 GiB).
  WARNING: You have not turned on protection against thin pools running out of space.
  WARNING: Set activation/thin_pool_autoextend_threshold below 100 to trigger automatic extension of thin pools before they get full.
  Logical volume "thin_vol" created.
  
[root@serverA ~]# lvs
  LV        VG      Attr       LSize  Pool      Origin Data%  Meta%  Move Log Cpy%Sync Convert
  root      cs      -wi-ao---- 16.41g
  swap      cs      -wi-ao----  2.00g
  thin_pool thin_vg twi-aotz--  4.50g                  0.00   10.64
  thin_vol  thin_vg Vwi-a-tz--  5.00t thin_pool        0.00
  wshare    wgroup  -wi-ao----  2.00g
 
[root@serverA ~]# lvs
  LV        VG      Attr       LSize  Pool      Origin Data%  Meta%  Move Log Cpy%Sync Convert
  root      cs      -wi-ao---- 16.41g
  swap      cs      -wi-ao----  2.00g
  thin_lv   thin_vg Vwi-a-tz--  5.00t thin_pool        0.00
  thin_pool thin_vg twi-aotz--  4.50g                  0.00   10.64
  wshare    wgroup  -wi-ao----  2.00g
 
# File system
[root@serverA ~]# mkfs -t xfs /dev/thin_vg/thin_vol
meta-data=/dev/thin_vg/thin_vol  isize=512    agcount=32, agsize=41943040 blks
         =                       sectsz=512   attr=2, projid32bit=1
         =                       crc=1        finobt=1, sparse=1, rmapbt=0
         =                       reflink=1    bigtime=1 inobtcount=1 nrext64=0
data     =                       bsize=4096   blocks=1342177280, imaxpct=5
         =                       sunit=16     swidth=16 blks
naming   =version 2              bsize=4096   ascii-ci=0, ftype=1
log      =internal log           bsize=4096   blocks=521728, version=2
         =                       sectsz=512   sunit=16 blks, lazy-count=1
realtime =none                   extsz=4096   blocks=0, rtextents=0
Discarding blocks...Done.
[root@serverA ~]# blkid /dev/thin_vg/thin_vol
/dev/thin_vg/thin_vol: UUID="468b9972-817f-41ae-8136-27ee87cbb614" TYPE="xfs"
 
# Mounting
[root@serverA ~]# vim /etc/fstab
/dev/thin_vg/thin_vol	/mnt/thin_vol	xfs	defaults	0	0
 
[root@serverA ~]# systemctl daemon-reload
[root@serverA ~]# mount -a
[root@serverA ~]# lsblk
NAME                        MAJ:MIN RM  SIZE RO TYPE MOUNTPOINTS
...
nvme0n4                     259:7    0    5G  0 disk
├─thin_vg-thin_pool_tmeta   253:3    0    8M  0 lvm
│ └─thin_vg-thin_pool-tpool 253:5    0  4.5G  0 lvm
│   ├─thin_vg-thin_pool     253:6    0  4.5G  1 lvm
│   └─thin_vg-thin_vol      253:7    0    5T  0 lvm  /mnt/thin_vol
└─thin_vg-thin_pool_tdata   253:4    0  4.5G  0 lvm
  └─thin_vg-thin_pool-tpool 253:5    0  4.5G  0 lvm
    ├─thin_vg-thin_pool     253:6    0  4.5G  1 lvm
    └─thin_vg-thin_vol      253:7    0    5T  0 lvm  /mnt/thin_vol

Q28: On serverA, set a merged tuned profile using the the powersave and virtual-guest profiles.

 
[root@serverA ~]# rpm -q tuned
tuned-2.24.0-1.el9.noarch
[root@serverA ~]# systemctl start tuned.service
[root@serverA ~]# systemctl status tuned.service
 
[root@serverA ~]# tuned-adm profile powersave virtual-guest
[root@serverA ~]# tuned-adm active
Current active profile: powersave virtual-guest

Q29: On serverA, as the user cindy, create a container image from docker.io/library/httpd with the tag web_image.

 
[root@serverA ~]# rpm -q container-tools
container-tools-1-14.el9.noarch
 
[root@serverA ~]# loginctl enable-linger cindy
[root@serverA ~]# hostname -I
192.168.208.138
[root@serverA ~]# ssh cindy@192.168.208.138
The authenticity of host '192.168.208.138 (192.168.208.138)' can't be established.
ED25519 key fingerprint is SHA256:HOPA4UyrPYpCEWcP4vMfeocqZn9r5fEBYgg9+lXNyeY.
This host key is known by the following other names/addresses:
    ~/.ssh/known_hosts:1: 192.168.208.137
Are you sure you want to continue connecting (yes/no/[fingerprint])? yes
Warning: Permanently added '192.168.208.138' (ED25519) to the list of known hosts.
cindy@192.168.208.138's password:
 
# Configure registries.conf if not present
[cindy@serverA containers]$ pwd
/home/cindy/.config/containers
[cindy@serverA containers]$ cat registries.conf
unqualified-search-registries =["docker.io","quay.io"]
[[registry]]
insecure = true
blocked = false
location = "docker.io"
 
[cindy@serverA ~]$ vim Containerfile
[cindy@serverA ~]$ cat Containerfile
FROM docker.io/library/httpd
 
[cindy@serverA ~]$ podman build -t web_image .
STEP 1/1: FROM docker.io/library/httpd
Trying to pull docker.io/library/httpd:latest...
Getting image source signatures
Copying blob 0ffcdbb5bd41 done   |
Copying blob 14c9d9d19932 done   |
Copying blob 4f4fb700ef54 done   |
Copying blob f5db40045454 done   |
Copying blob ac0ad684e55d done   |
Copying blob b59792d2b7f1 done   |
Copying config a3e79aafef done   |
Writing manifest to image destination
COMMIT web_image
--> a3e79aafef7f
Successfully tagged localhost/web_image:latest
Successfully tagged docker.io/library/httpd:latest
a3e79aafef7f07a3a11d94f546220d8189719a5143d4bbda9568e48ffbac4a9d
 
[cindy@serverA ~]$ podman images
REPOSITORY               TAG         IMAGE ID      CREATED       SIZE
localhost/web_image      latest      a3e79aafef7f  2 months ago  182 MB
docker.io/library/httpd  latest      a3e79aafef7f  2 months ago  182 MB

Q30: From the newly created image, deploy a container as a service with the container name cindy_web.The web config files should map to ~/web_files, and the local port of 8000 should be mapped to the container's port 80. Create a default page that says "Welcome to Cindy's Web Server!". The service should be enabled and the website should be accessible.

 
 
# Add port in http.conf from root 
[root@serverA ~]# vim /etc/httpd/conf/httpd.conf
Listen 8000
 
# Tell Selinux 
[root@serverA ~]# semanage port -a -t http_port_t -p tcp 8000
[root@serverA ~]# semanage port -l | grep 8000
http_port_t                    tcp      8000, 82, 7788, 5566, 80, 81, 443, 488, 8008, 8009, 8443, 9000
soundd_port_t                  tcp      8000, 9433, 16001
 
# Run the container in port 8000 / tell selinux about port / make volume ~/web_files
[cindy@serverA ~]$ podman run -d --name cindy_web -v /home/cindy/web_files:/usr/local/apache2/htdocs/:Z -p 8000:80 localhost/web_image:latest
dae967e62ceb5131a5a78e27edbccf17b92a4391534feb7a3c4e00f70a258f9d
[cindy@serverA ~]$ podman ps -a
CONTAINER ID  IMAGE                       COMMAND           CREATED        STATUS        PORTS                         NAMES
dae967e62ceb  localhost/web_image:latest  httpd-foreground  3 seconds ago  Up 4 seconds  0.0.0.0:8000->80/tcp, 80/tcp  cindy_web
[cindy@serverA ~]$ curl localhost:8000
<h1>Welcome to Cindys Web Server!</h1>
 
# Run container as a service 
[cindy@serverA user]$ pwd
/home/cindy/.config/systemd/user
 
[cindy@serverA user]$ ls
container-cindy_web.service
 
[cindy@serverA user]$ podman stop cindy_web
 
[cindy@serverA user]$ systemctl --user stop container-cindy_web.service
[cindy@serverA user]$ systemctl --user start container-cindy_web.service
[cindy@serverA user]$ systemctl --user status container-cindy_web.service