Omer Cakmak

Fix kickstart clearpart not working on RHEL 10: scope disks with ignoredisk and clearpart --drives, wipe old LVM with a %pre script, and validate storage before autopart.

Kickstart %pre and %pre-install script examples on RHEL 10: --log, --interpreter, disk wipe before clearpart, NIC inventory, and copying logs with %post --nochroot.

Kickstart %post script examples on RHEL 10: chrooted post-install tasks, --nochroot log copy, --interpreter for Python and Bash, systemctl enable, and lab verification script.

Create and edit Linux text files with Vim, Nano, touch, redirection, search and replace, backups, and safe configuration edits from the command line.

Extend a logical volume with lvextend, grow PV capacity with pvresize or vgextend when the volume group is full, grow XFS with xfs_growfs or ext4 with resize2fs, and verify both layers.

Install Nginx, MariaDB, PHP, and PHP-FPM on Rocky Linux, RHEL, AlmaLinux, or Oracle Linux, then verify the complete LEMP stack with a PHP database test.

Restart or reload cron in Linux with systemctl restart cron on Ubuntu and Debian or crond on RHEL and Rocky Linux, and when a reload is actually needed.

Install JasperReports Server on RHEL, Rocky Linux, AlmaLinux, CentOS Stream, Oracle Linux, or Fedora using the evaluation binary installer with bundled components or a production WAR deployment on supported Tomcat and …

List users in Linux with getent, /etc/passwd, who, and id. Filter normal and system accounts, see logged-in sessions, and check whether a user exists on Ubuntu and RHEL.

List groups in Linux with getent, groups, id, and /etc/group. Check user group membership, list group members, and compare primary vs supplementary groups.

Install Node.js on Ubuntu with apt nodejs, NodeSource setup scripts, NVM for multiple versions, or the official nodejs.org linux-x64 tar.xz under /opt, verify with node --version and npm --version, and uninstall per …

sort reads lines from files or stdin and prints them in order. Use it for log lines, CSV columns, version strings, and pipeline output from ls, awk, or find — then pair with uniq to drop duplicates.

rmmod removes loadable kernel modules from a running Linux kernel. Use it to unload drivers you loaded for testing; modprobe -r is the higher-level alternative that handles dependencies.

List obsolete packages on Ubuntu with apt list ?obsolete, preview removal with apt-get -s, purge safely after do-release-upgrade, and distinguish obsolete packages from autoremove and rc config cleanup.

Downgrade Ubuntu 21.04 (Hirsute Hippo) to 20.04 LTS (Focal Fossa) with apt pinning, sources.list retargeting, and aptitude dist-upgrade—no data loss under /home when the run completes, plus dpkg recovery, reboot checks, …

Install Plex Media Server on Debian 11, 12, or 13 from the official repo.plex.tv APT repository or a .deb download, start plexmediaserver with systemctl, open port 32400, complete setup at http://127.0.0.1:32400/web, …

Ubuntu is a free and open-source operating system that is widely used in desktops and servers. It is known for its stability, security, and ease of use. One

In this tutorial we will share steps and different methods to install EPE repo in Rocky Linux

Install NordVPN on Ubuntu with the official install.sh script or Snap, add your user to the nordvpn group, log in with nordvpn login, connect with nordvpn connect, and fix Permission denied nordvpnd.sock and LAN …

Remove unused packages on Ubuntu with apt autoremove for orphaned dependencies, apt clean and autoclean for download cache, purge rc config leftovers, protect apps with apt-mark manual, and prune old Snap …

Install Wireshark on Ubuntu with sudo apt install wireshark from universe, allow non-root capture via wireshark-common debconf, add your user to the wireshark group, and optionally install tshark for CLI-only capture on …

Install Slack on Ubuntu with Slack Packagecloud APT repo, official slack-desktop .deb from slack.com, or sudo snap install slack. Launch with slack, update per method, and remove only one desktop package at a time.

Install Rscript on Ubuntu with sudo apt install r-base from universe, optionally add the CRAN apt repository on supported LTS releases, verify with Rscript --version, run example.R from the shell or cron, and uninstall …

List installed packages on Ubuntu with apt list --installed, dpkg -l, snap list, and apt-mark showmanual. Search one package, count totals, export a list for another machine, and check upgradable packages.

Install Plex Media Server on Ubuntu from the official repo.plex.tv APT repository or a .deb download, start plexmediaserver with systemctl, open port 32400, complete setup at http://127.0.0.1:32400/web, and fix plex user …

Install MongoDB 8.0 Community on Ubuntu from the official mongodb-org repo with gpg keyring (jammy/noble/focal), start mongod with systemctl, connect with mongosh, install shell-only for Atlas, and fix libssl1.1, AVX, …

Install Terminator on Ubuntu with sudo apt install terminator from universe (2.1.4 on 25.04), verify with which terminator and dpkg, set the default x-terminal-emulator, split panes with Ctrl+Shift+O/E, and fix DISPLAY …

Install OpenCV on Ubuntu with sudo apt install libopencv-dev python3-opencv (4.10.0 on 25.04), verify with import cv2 and pkg-config opencv4, use pip opencv-python in a venv for newer wheels, or build from source when …

Install Minecraft Java Edition on Ubuntu from the official Minecraft.deb (launcher 2.1.3), openjdk-21-jre-headless, or the Minecraft.tar.gz binary: sign in with a Microsoft account, launch minecraft-launcher, and …

Linux rm has no built-in undo and does not use Trash by default, but you can sometimes recover deleted files—stop writes to the disk first, then try backups, open file handles via /proc, carving tools like Foremost and …