Opbzil - classnotes:rh134

automount

Anonymous (anonymous@undisclosed.example.com) — 2025-10-07T10:14:17+00:00

Automount used to automatically mount devices/shares 2 types of automapping direct and indirect. direct mount is when a file system mounts to an unchanging, known mount point location. Almost all the file system mounts that you configured, indirect

bash

Anonymous (anonymous@undisclosed.example.com) — 2025-10-07T10:14:17+00:00

Write Simple Bash Scripts in vim enable line numbering with esc :set nu using awk awk is used to get bits of files for example awk -F: `{print $1}` prints out the first entry (from the $1) of a file that uses : as a separator Loops for The structure is

boot-issues

Anonymous (anonymous@undisclosed.example.com) — 2025-10-07T10:14:17+00:00

Repair File-system Issues at Boot to fix stuff you need to get in to emergency mode. For this you will need the root password To boot into emergency to you to interrupt the boot and edit the line in grub that begins with linux. append systemd.unit=emergency.target

boot

Anonymous (anonymous@undisclosed.example.com) — 2025-10-07T10:14:17+00:00

Control the Boot Process identifyng the target commands what they do systemctl get-default shows the default target that system boots to systemctl list-units -t targets list of all unis of type target systemctl list-dependecies graphical.target

containers

Anonymous (anonymous@undisclosed.example.com) — 2025-10-07T10:14:17+00:00

Run Containers a container is a running instance of a container image a container image is a single file (tar) loaded with metadata anf has all files needed by your application it also has an entry point (in metadata) this is the command needed to start container)

firewall

Anonymous (anonymous@undisclosed.example.com) — 2025-10-07T10:14:17+00:00

Manage Network Security you interface with the firewall using the firewall-cmd it makes changes to the file /etc/firewalld/zones/public.xml here are some options command option what it does --get-default-zone List the default zone --list-all

kickstarter

Anonymous (anonymous@undisclosed.example.com) — 2025-10-07T10:14:17+00:00

Automate Installation with Kickstart Redhat has a tool you can use to create kickstarter files you can get it at

layered-storage

Anonymous (anonymous@undisclosed.example.com) — 2025-10-07T10:14:17+00:00

Manage Layered Storage Using Stratis

lvm

Anonymous (anonymous@undisclosed.example.com) — 2025-10-07T10:14:17+00:00

Manage Storage Stack interestingly enough he does not create partitions before creatting the pv here is a lvresize comand lvresize -r -L 2G /dev/vg_DB/lv_maria -r is to extend filesystem -L specifies the final size of LV and the last bit i cnonical path of lv

nfs

Anonymous (anonymous@undisclosed.example.com) — 2025-10-07T10:14:17+00:00

Access Network-Attached Storage consists of 2 components nfs server and nfs client nfs defaults now to version 4 which only uses port 2049 so need to run command firewall-cmd --add-service nfs --permanent firewall-cmd --add-service nfs On the NFS server need to install nfs-utils and enable the nfs-server

recurring

Anonymous (anonymous@undisclosed.example.com) — 2025-10-07T10:14:17+00:00

Schedule Recurring Tasks Schedule Recurring User Jobs Use the crontab command to manage scheduled jobs list of commands that a user can use to manage their jobs crontab -l list the jobs from current user crontab -r remove all jobs from current user

reset-root

Anonymous (anonymous@undisclosed.example.com) — 2025-10-07T10:14:17+00:00

Reset the Root Password To access that root shell, follow these steps: Reboot the system. * Interrupt the boot-loader countdown by pressing any key, except Enter. * Move the cursor to the rescue kernel entry to boot (the entry with the rescue word in its name).

selinux-ports

Anonymous (anonymous@undisclosed.example.com) — 2025-10-07T10:14:17+00:00

Control SELinux Port Labeling SELinux Port Labeling In addition to file context and process type labeling, SELinux labels network ports with an SELinux context. SELinux controls network access by labeling the network ports and including rules in a service's targeted policy. For example, the SSH targeted policy includes the 22/TCP port with an ssh_port_t port context label. In the HTTP policy, the default 80/TCP and 443/TCP ports use an http_port_t port context label.

selinux

Anonymous (anonymous@undisclosed.example.com) — 2025-10-07T10:14:17+00:00

Manage SELinux Security Its a form of mandatory access control. Its enabled by default Context Control Selinux File Context Adjust SELinux Policy with Booleans Investigate and Resolve SELinux Issues

storagr

Anonymous (anonymous@undisclosed.example.com) — 2025-10-07T10:14:17+00:00

Manage Basic Storage Linux Partitions SWap Manage Basic Storage

system-schedule

Anonymous (anonymous@undisclosed.example.com) — 2025-10-07T10:14:17+00:00

Schedule Recurring System Jobs uses the /etc/crontab file if the system is not available anacron checks to see that was missed and will run it. you also have the /etc/cron.daily /etc/cron/weekly and /etc/cron/monthly you can place executable files on those directories and they will be executed. You do not have control of the exact time when its done

systemlogs

Anonymous (anonymous@undisclosed.example.com) — 2025-10-07T10:14:17+00:00

Describe System Log Architecture The systemd-journald service is at the heart of the operating system event logging architecture. The systemd-journald service collects event messages from many sources: The rsyslog service reads syslog messages that the systemd-journald service receives from the journal when they arrive. The rsyslog service then processes the syslog events, and records them to its log files or forwards them to other services according to its own configuration.

tar-files

Anonymous (anonymous@undisclosed.example.com) — 2025-10-07T10:14:17+00:00

Archive and Transfer Files tar tar used to create and extract files Moving Files Around moving files around Synchronize Files Between Systems Securely Synchronize Files Between Systems Securely

tasks

Anonymous (anonymous@undisclosed.example.com) — 2025-10-07T10:14:17+00:00

Schedule Future Tasks One jobs Uses the atd service uses the at command example at 21:03 < myscript or it can be interactive like [student@servera ~]$ at -q g teatime warning: commands will be executed using /bin/sh at> echo "It's teatime" >> /home/student/tea.txt at> Ctrl+d job 2 at Fri Feb 17 16:00:00 2023

tune

Anonymous (anonymous@undisclosed.example.com) — 2025-10-07T10:14:17+00:00

Tune System Performance Adjust Tuning Profiles Linux Process Scheduling

virtual

Anonymous (anonymous@undisclosed.example.com) — 2025-10-07T10:14:17+00:00

Install and Configure Virtual Machines Preparation install appropriate software dnf group install "Virtualization Host" this package helps manage the Vms and make sure cockpit is enabled systemctl enable --now cockpit.socket to make sure all is installed ok run the command