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)

  1. pv
  2. vg
  3. 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
  4. 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
All systems normal

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