Linux Commands
Command references for core Linux tools, syntax, examples, and practical one-liners.
How to Check the Kernel Version in Linux
Three quick ways to find the Linux kernel version from the command line: uname, hostnamectl, and /proc/version.
file Command in Linux: Determine File Types
Identify file types from the command line using the Linux file command. Covers basic usage, MIME types, compressed files, symlinks, and the magic database.
Chattr Command in Linux (File Attributes)
How to use chattr and lsattr to set and view file attributes in Linux, including immutable files, append-only logs, and recursive protection.
env Command in Linux: Show and Set Environment Variables
The env command prints environment variables and runs programs with a modified environment. This guide covers env syntax, running commands with custom variables, clean environments, and portable shebangs.
nmap Command in Linux with Practical Examples
Use the nmap command in Linux to discover hosts, scan ports, detect services, and understand common scan options such as -sn, -Pn, and -sV.
id Command in Linux: Display User and Group Information
The id command prints real and effective user IDs, group IDs, and supplemental group memberships for any user on a Linux system.
sed Delete Lines: Remove Lines by Number, Pattern, or Range
Remove lines from files with sed using line numbers, patterns, ranges, and regular expressions. Covers preview mode, in-place editing, and common recipes.
How to Rename Directories in Linux
Rename single or multiple directories from the Linux command line using the mv command, for loops, and the rename utility.
w Command in Linux: Show Logged-In Users and Activity
Learn how to use the w command in Linux to see logged-in users, idle time, load averages, and what each user is doing.
sysctl Command in Linux: View and Change Kernel Parameters
Learn how to use the sysctl command to view, set, and persist Linux kernel parameters, with practical examples for common settings.
whereis Command in Linux: Find Binary, Source, and Man Pages
The Linux whereis command locates the binary, source, and manual page files for a given command. This guide covers all options with practical examples.
git clone: Clone a Repository
How to use git clone to copy a remote or local repository, clone a specific branch, and create shallow clones, with examples for HTTPS and SSH.
How to Copy Files and Directories in Linux
Step-by-step guide to copying files and directories in Linux with the cp and rsync commands. Covers recursive copies, preserving permissions, and common examples.
jobs Command in Linux: List and Manage Background Jobs
The jobs command lists background and suspended processes in the current shell session. This guide covers syntax, options, job specifications, and practical examples.
dmesg Command in Linux: Read and Filter Kernel Messages
How to use the dmesg command in Linux to read kernel ring buffer messages, filter by log level and facility, display human-readable timestamps, and watch for new events in real time.
paste Command in Linux: Merge Lines from Files
Use the paste command in Linux to merge lines from multiple files side by side, change delimiters, and serialize output with practical examples.
git stash: Save and Restore Uncommitted Changes
How to use git stash to temporarily save uncommitted changes, switch branches, and restore your work — with examples for stashing untracked files, named stashes, and partial stashes.
rpm Command in Linux: Install, Query, and Verify Packages
Use the rpm command in Linux to install, upgrade, remove, query, and verify RPM packages on Fedora, RHEL, AlmaLinux, Rocky Linux, and other RPM-based distributions.
How to Transfer Files with Rsync over SSH
Use rsync over SSH to copy and synchronize files and directories between local and remote systems, with examples for custom ports, dry runs, compression, and progress display.
pstree Command in Linux: View the Process Tree
Use the pstree command in Linux to display running processes as a tree, show PIDs and PGIDs, trace parent processes, and highlight specific branches.
