Preparation Set 3
Q1: Configure network and set the static parameters
- IP-ADDRESS= 192.168.208.138
- NETMASK= 255.255.255.0
- GATEWAY= 192.168.208.2
- (DNS) Nameserver= 192.168.208.2
- Domain Name= domainX.example.com
- hostname= node1.domainX.example.com
[root@serverA ~]# hostnamectl set-hostname node1.domainX.example.com [root@node1 ~]# nmcli conn modify serverAnet ipv4.addresses 192.168.208.138/24 ipv4.dns 192.168.208.2 ipv4.gateway 192.168.208.2 ipv4.method manual [root@node1 ~]# systemctl restart NetworkManager [root@node1 ~]# cat /etc/hosts 192.168.208.138 node1.domainX.example.com
Q2. Configure YUM repos with the given link (2repos: 1st is BaseOS and 2nd is AppStream)
[root@node1 yum.repos.d]# pwd /etc/yum.repos.d [root@node1 yum.repos.d]# cat appstream.repo [appstream] name = appstream baseurl = http://192.168.208.137/softwares/AppStream enabled = 1 gpgcheck = 0 [root@node1 yum.repos.d]# cat baseos.repo [baseos] name = baseos baseurl = http://192.168.208.137/softwares/BaseOS enabled = 1 gpgcheck = 0
Q3: Debug SELinux - A web server running on non standard port 82 is having issues serving content, Debug and fix the issues.
[root@node1 ~]# vim /etc/httpd/conf/httpd.conf Listen 8200 # [root@node1 ~]# cat /etc/ssh/sshd_config Search the code semanage [root@node1 ~]# semanage port -a -t http_port_t -p tcp 8200 # Check for port [root@node1 ~]# semanage port -l | grep 8200 http_port_t tcp 8200, 8000, 82, 7788, 5566, 80, 81, 443, 488, 8008, 8009, 8443, 9000 trivnet1_port_t tcp 8200 trivnet1_port_t udp 8200 [root@node1 ~]# systemctl start httpd [root@node1 ~]# systemctl enable httpd [root@node1 ~]# systemctl status httpd [root@node1 ~]# firewall-cmd --permanent --add-port=82/tcp [root@node1 ~]# firewall-cmd --reload
Q4. Create User accounts with supplementry group.
- create the group a named "sysadms".
- create users as named "natasha" and "harry", will be the supplementry group "sysadms".
- cerate a user as named "sarah", should have non-interactive shell and it should be not the member of "sysadms".
- password for all users should be "trootent"
[root@node1 ~]# groupadd sysadms [root@node1 ~]# useradd natasha -G sysadms [root@node1 ~]# useradd harry -G sysadms [root@node1 ~]# useradd sarah -s /sbin/nologin [root@node1 ~]# cat /etc/passwd | grep natasha harry sarah [root@node1 ~]# cat /etc/passwd | grep natasha natasha:x:5126:5128::/home/natasha:/bin/bash [root@node1 ~]# cat /etc/passwd | grep harry harry:x:5127:5129::/home/harry:/bin/bash [root@node1 ~]# cat /etc/passwd | grep sarah sarah:x:5128:5130::/home/sarah:/sbin/nologin [root@node1 ~]# passwd natasha [root@node1 ~]# passwd harry [root@node1 ~]# passwd sarah
Q5. Configure a cron job that runs every 2minutes and executes: logger "EX200 in progress" as the user natasha.
[root@node1 etc]# vim cron.allow [root@node1 etc]# cat cron.allow natasha [root@node1 etc]# su - natasha Last login: Thu Oct 10 19:30:51 CST 2024 on pts/1 [natasha@node1 ~]$ crontab -e no crontab for natasha - using an empty one crontab: installing new crontab [natasha@node1 ~]$ crontab -l */2 * * * * logger "EX200 in progress"
Q6. Create a collaborative Directory.
- Create the Directory "/home/manager" with the following characteristics
- Group ownership of "/home/manager" should go to "sysadms" group
- The directory should have full permission for all members of "sysadms" group but not to the other users except "root"
- Files created in future under "/home/manager" should get the same group ownership
[root@node1 home]# chown :sysadms manager [root@node1 home]# ls -ld manager drwxr-xr-x. 2 root sysadms 6 Oct 10 19:54 manager [root@node1 home]# chmod g+rwx manager [root@node1 home]# ls -ld manager drwxrwxr-x. 2 root sysadms 6 Oct 10 19:54 manager [root@node1 home]# chmod o-rwx manager [root@node1 home]# ls -ld manager/ drwxrwx---. 2 root sysadms 6 Oct 10 19:54 manager/ [root@node1 home]# chmod g+s manager [root@node1 home]# ls -ld manager drwxrws---. 2 root sysadms 6 Oct 10 19:54 manager [root@node1 home]# cd manager [root@node1 manager]# touch f1 f2 [root@node1 manager]# ls -lh total 0 -rw-r--r--. 1 root sysadms 0 Oct 10 20:09 f1 -rw-r--r--. 1 root sysadms 0 Oct 10 20:09 f2
Q7. Configure NTP - Synchronize time of your system with the server 'us.pool.ntp.org'
[root@node1 ~]# rpm -q chrony chrony-4.6-1.el9.aarch64 [root@node1 ~]# systemctl status chronyd.service [root@node1 ~]# vim /etc/chrony.conf server us.pool.ntp.org iburst [root@node1 ~]# systemctl restart chronyd.service [root@node1 ~]# timedatectl set-ntp true [root@node1 ~]# chronyc sources MS Name/IP address Stratum Poll Reach LastRx Last sample =============================================================================== ^* ntp1a.versadns.com 1 6 17 44 -3869us[-2737us] +/- 162ms
Q8. Configure AutoFS - All remoteuserX home directory is exported via NFS, which is available on utility.example.com(172.24.10.100) and your NFS-exports directory is /home/remoteuserX for remoteuserX
- remoteuserX's home directory is utility.example.com:/rhome/remoteuserX, where X is your station number and benath as /rhome/remoteuser5
- remoteuserX's home directory should be automounted autofs service.
- home directories must be writable by their users
[root@node1 ~]# rpm -q autofs autofs-5.1.7-58.el9.aarch64 [root@node1 ~]# systemctl start autofs [root@node1 ~]# systemctl enable autofs [root@node1 ~]# vim /etc/auto.master [root@node1 ~]# cat /etc/auto.master /home/rhome /etc/auto.nfs --timeout=300 [root@node1 ~]# vim /etc/auto.nfs [root@node1 ~]# cat /etc/auto.nfs remoteuser5 -rw,soft,sync 192.168.208.137:/rhome/remoteuser5 [root@node1 remoteuser5]# pwd [root@node1 remoteuser5]# ls f1 f2 f3
Q9. Create a container image from the provided link.
- create a container image from "http://utility.example.com/container/Containerfile" name it as 'monitor' with user athena
- login to 'registry.lab.example.com' through "admin" and "redhat321" ->find it out credentials from Instructions page
[root@node1 ~]# loginctl enable-linger athena [root@node1 ~]# su - athena [athena@node1 ~]$ rpm -q container-tools container-tools-1-14.el9.noarch [athena@node1 containers]$ pwd /home/athena/.config/containers [athena@node1 containers]$ cat registries.conf unqualified-search-registries = ["docker.io"] [[registry]] insecure = false blocked = false location = 'docker.io' [athena@node1 ~]$ podman build -t monitor . 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 f5db40045454 done | Copying blob 4f4fb700ef54 done | Copying blob ac0ad684e55d done | Copying blob b59792d2b7f1 done | Copying config a3e79aafef done | Writing manifest to image destination COMMIT monitor --> a3e79aafef7f Successfully tagged localhost/monitor:latest Successfully tagged docker.io/library/httpd:latest a3e79aafef7f07a3a11d94f546220d8189719a5143d4bbda9568e48ffbac4a9d [athena@node1 ~]$ podman images REPOSITORY TAG IMAGE ID CREATED SIZE localhost/monitor latest a3e79aafef7f 2 months ago 182 MB docker.io/library/httpd latest a3e79aafef7f 2 months ago 182 MB
Q10. Create rootless container and do volume mapping which they asked you in the question and run container as a service from normal user account, the service must be enable so it could start automatically after reboot
- Create a container named as '' using the previously created container image from previous question 'monitor'
- Map the '/opt/processed' to container '/opt/outgascii2pdfoing
- Map the '/opt/files' to container '/opt/incoming'
- Create systemd service as container-ascii2pdf.service
- Make service active after all server reboots.
[root@node1 opt]# chown -R athena:athena /opt/files [root@node1 opt]# chown -R athena:athena /opt/processed [athena@node1 ~]$ podman run -d -v /opt/processed:/opt/outgascii2pdfoing:Z -v /opt/files:/opt/incoming:Z --name ascii2pdf localhost/monitor:latest 647b7a7f532cb52575e92a93bfded7b845cb9202e0cca3158be4ad0a06fb96b6 [athena@node1 ~]$ podman ps -a CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES 647b7a7f532c localhost/monitor:latest httpd-foreground 4 seconds ago Up 4 seconds 80/tcp ascii2pdf [athena@node1 user]$ pwd /home/athena/.config/systemd/user [athena@node1 user]$ podman generate systemd --name ascii2pdf --files --new DEPRECATED command: It is recommended to use Quadlets for running containers and pods under systemd. Please refer to podman-systemd.unit(5) for details. /home/athena/.config/systemd/user/container-ascii2pdf.service [athena@node1 user]$ ls container-ascii2pdf.service [athena@node1 user]$ systemctl --user enable container-ascii2pdf.service Created symlink /home/athena/.config/systemd/user/default.target.wants/container-ascii2pdf.service → /home/athena/.config/systemd/user/container-ascii2pdf.service. [athena@node1 user]$ systemctl --user start container-ascii2pdf.service [athena@node1 user]$ podman ps -a CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES 1b9173e5e933 localhost/monitor:latest httpd-foreground 9 seconds ago Up 9 seconds 80/tcp ascii2pdf [athena@node1 ~]$ systemctl --user status container-ascii2pdf.service ● container-ascii2pdf.service - Podman container-ascii2pdf.service Loaded: loaded (/home/athena/.config/systemd/user/container-ascii2pdf.service; enabled; preset: disabled) Active: active (running) since Thu 2024-10-10 21:24:18 CST; 33s ago Docs: man:podman-generate-systemd(1) Main PID: 15914 (conmon) Tasks: 2 (limit: 22565) Memory: 16.2M CPU: 132ms CGroup: /user.slice/user-5129.slice/user@5129.service/app.slice/container-ascii2pdf.service ├─15912 /usr/bin/pasta --config-net --dns-forward 169.254.0.1 -t none -u none -T none -U none --no-map-gw --qui> └─15914 /usr/bin/conmon --api-version 1 -c 1b9173e5e9330936c1976c6837d097dbcfca8a494d9ee8d46dc99e1256cf625c -u >
Q11. Find a string 'ich' from "/usr/share/dict/words" and put it into /root/lines
file.
[root@node1 ~]# grep ich /usr/share/dict/words >/root/lines
Q12. create an archive '/root/backup.tar.bz2' of /usr/local directory and
compress it with bzip2
[root@node1 ~]# tar -jcvf backup.tar.bz2 /usr/local/
Q13. script. Store the search result of all files in the /usr/share directory that is greater than 30k and less than 50k in the /mnt/freespace/search.txt file
[root@node1 ~]# find /usr/share -type f -size +30k -size -50k >/mnt/freespace/search.txt [root@node1 ~]# cat /mnt/freespace/search.txt
Q14. Resize a logical Volume - Resize the logical volume "mylv" so that after reboot size should be in between 290MB to 330MB
[root@node1 ~]# lvextend -L 310M /dev/myvg/mylv [root@node1 ~]# resize2fs /dev/mapper/myvg-mylv
Q15. Add a swap partition of 512MB and mount it permanently
[root@node1 ~]# vim /etc/fstab [root@node1 ~]# tail -1 /etc/fstab /dev/nvme0n3p1 swap swap defaults 0 0 [root@node1 ~]# mkswap /dev/nvme0n3p1 mkswap: /dev/nvme0n3p1: warning: wiping old xfs signature. Setting up swapspace version 1, size = 512 MiB (536866816 bytes) no label, UUID=cf881383-bcf5-4a87-9c3f-6fd8bbf0ad7d [root@node1 ~]# systemctl daemon-reload [root@node1 ~]# swapon -a [root@node1 ~]# lsblk nvme0n3 259:6 0 6G 0 disk └─nvme0n3p1 259:10 0 512M 0 part [SWAP]
Q16. Create logical volume and mount it permanently
- Create a logical volume of name/mnt/wshare "wshare" from a volume group name "wgroup" physical extents of 16M and logical volume should have size of 50extents
- Mount logical volume with and format with ext3 filesystem
[root@node1 ~]# gdisk /dev/nvme0n3 Command (? for help): n Partition number (2-128, default 2): First sector (34-12582878, default = 1050624) or {+-}size{KMGTP}: Last sector (1050624-12582878, default = 12582878) or {+-}size{KMGTP}: +3G Current type is 8300 (Linux filesystem) Hex code or GUID (L to show codes, Enter = 8300): L Type search string, or <Enter> to show all codes: LV 8e00 Linux LVM 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 1050623 512.0 MiB 8200 Linux swap 2 1050624 7342079 3.0 GiB 8E00 Linux LVM Command (? for help): w Do you want to proceed? (Y/N): y The operation has completed successfully. # Create PV [root@node1 ~]# pvcreate /dev/nvme0n3p2 Physical volume "/dev/nvme0n3p2" successfully created. [root@node1 ~]# pvs PV VG Fmt Attr PSize PFree /dev/nvme0n1p3 cs lvm2 a-- 18.41g 0 /dev/nvme0n2 myvg lvm2 a-- <5.00g <4.00g /dev/nvme0n3p2 lvm2 --- 3.00g 3.00g # Create VG [root@node1 ~]# vgcreate -s 16M wgroup /dev/nvme0n3p2 Volume group "wgroup" successfully created [root@node1 ~]# vgs VG #PV #LV #SN Attr VSize VFree cs 1 2 0 wz--n- 18.41g 0 myvg 1 1 0 wz--n- <5.00g <4.00g wgroup 1 0 0 wz--n- 2.98g 2.98g [root@node1 ~]# vgdisplay wgroup --- Volume group --- VG Name wgroup 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 2.98 GiB PE Size 16.00 MiB Total PE 191 Alloc PE / Size 0 / 0 Free PE / Size 191 / 2.98 GiB VG UUID qiffjO-C26Z-71T7-Bzsm-hoVf-b7SU-1d1btA # Create LV [root@node1 ~]# lvcreate -l 50 --name wshare wgroup Logical volume "wshare" created. [root@node1 ~]# 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 mylv myvg -wi-a----- 1.00g wshare wgroup -wi-a----- 800.00m [root@node1 ~]# lvdisplay /dev/wgroup/wshare --- Logical volume --- LV Path /dev/wgroup/wshare LV Name wshare VG Name wgroup LV UUID 8v3B93-SRQ0-FGyJ-m7tz-nn1Z-l0j7-e5SzN6 LV Write Access read/write LV Creation host, time node1.domainX.example.com, 2024-10-11 08:57:17 +0800 LV Status available # open 0 LV Size 800.00 MiB Current LE 50 Segments 1 Allocation inherit Read ahead sectors auto - currently set to 8192 Block device 253:3 [root@node1 ~]# mkfs -t ext4 /dev/wgroup/wshare mke2fs 1.46.5 (30-Dec-2021) Creating filesystem with 204800 4k blocks and 51296 inodes Filesystem UUID: 32a56347-9075-4bba-ada5-ddf6da05a42b Superblock backups stored on blocks: 32768, 98304, 163840 Allocating group tables: done Writing inode tables: done Creating journal (4096 blocks): done Writing superblocks and filesystem accounting information: done [root@node1 ~]# vim /etc/fstab [root@node1 ~]# tail -1 /etc/fstab /dev/wgroup/wshare /mnt/wshare ext4 defaults 0 0 [root@node1 ~]# systemctl daemon-reload [root@node1 ~]# mount -a [root@node1 ~]# lsblk NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINTS nvme0n3 259:6 0 6G 0 disk ├─nvme0n3p2 259:5 0 3G 0 part │ └─wgroup-wshare 253:3 0 800M 0 lvm /mnt/wshare
Q17. Configure System Tuning: Choose the recommended 'tuned' profile for your system and set it as the default
[root@node1 ~]# rpm -q tuned tuned-2.24.0-1.el9.noarch [root@node1 ~]# systemctl status tuned.service [root@node1 ~]# tuned-adm active Current active profile: powersave [root@node1 ~]# tuned-adm recommend virtual-guest [root@node1 ~]# tuned-adm profile virtual-guest [root@node1 ~]# tuned-adm active Current active profile: virtual-guest