linux

Arch Linux Commands

Arch-Based Linux Command Cheat Sheet & Reference 🛠️

This document serves as a quick reference for common system administration, networking, and security auditing commands on Arch Linux and systems using the pacman package manager (like Manjaro).

1. SSH and File Permissions

Command	Purpose	Explanation
`ssh-keygen -R 192.168.0.1`	Remove SSH Key	Removes the host key for the specified IP from your `known_hosts` file. Use this if the remote server key changes.
`sudo chmod u+x my_script.sh`	Allow Execution	Adds the execute permission (`+x`) for the user (`u+`) who owns the file, making a script runnable.
`sudo chmod 644`	File Permissions	Owner can read/write; Group/Others can only read (standard file permission).
`sudo chmod 755`	Script/Directory Permissions	Owner can read/write/execute; Group/Others can read/execute (standard directory/script permission).

2. Package Management (`pacman` and AUR)

Command	Purpose	Explanation
`sudo pacman -Syu`	Sync, Refresh & Update	Syncs package lists (`y`) and upgrades the entire system.
`sudo pacman -S [package_name]`	Install Package	Syncs/Installs the specified package from the repositories.
`sudo pacman -R [package_name]`	Remove Package	Removes the specified package, but keeps its dependencies.
`sudo pacman -Rs [package_name]`	Remove Package & Deps	Removes the specified package and its unneeded surviving dependencies.
`pacman -Qk`	Check Package Integrity	Checks the integrity of installed packages (verifies file hash).
`pacman -Qs [search_term]`	Search Installed	Queries the installed packages for a specific string.
`pacman -Ss [search_term]`	Search Repositories	Searches the official repository package strings.
`sudo pacman -Sc`	Clear Package Cache	Clears the package cache, removing old versions of packages.
`yay -S [package_name]`	Install from AUR	Uses the common AUR helper `yay` to install packages from the Arch User Repository.

3. Diagnostics and System Info

Command	Purpose	Explanation
`ls -la /usr/folder1/folder2/`	Check Files/Folders	Lists all (`-a`) files in the path with long format details (`-l`).
`lsblk`	List Disks	Lists all block devices (drives and partitions) on the system.
`free -h`	Memory Usage	Displays free, used, and total system memory and swap space in a human-readable format.
`sudo iftop`	Network Traffic (General)	Displays network bandwidth usage on an interface in real-time.
`sudo nethogs`	Network Traffic (Per Process)	Displays which process/program is using the most network bandwidth.
`ncdu`	Disk Usage	An interactive ncurses utility for visualizing disk space usage.
`htop`	Process Viewer	An interactive, improved version of the `top` command for monitoring processes and resources.
`btop`	Modern Monitor	A feature-rich, visually appealing resource monitor.

4. Storage and File System Management

Command	Purpose	Explanation
`sudo pacman -S exfatprogs`	Install ExFAT Support	Installs the necessary utilities for managing ExFAT filesystems.
`sudo mount -t exfat /dev/sdXN /mnt/your_mount_point`	Mount ExFAT Drive	Mounts an ExFAT-formatted drive to the specified mount point. Replace `sdXN` with actual device (e.g., `sdb1`).

5. Network Configuration and Scanning

Command	Purpose	Explanation
`ip a`	View IP Addresses	Displays address information for all network interfaces (modern replacement for `ifconfig`).
`iw dev`	Wireless Info	Shows detailed information about wireless devices.
`sudo ip link set wlan1 down`	Disable Interface	Brings down the specified wireless interface.
`sudo ip link set wlan1 name wlan1mon`	Rename Interface	Renames the wireless interface (useful for monitor mode setup).
`airmon-ng`	Monitor Mode	Puts a wireless card into monitor mode for security auditing.
`sudo pacman -S arp-scan`	Install ARP Scan	Installs the `arp-scan` utility (not always pre-installed).
`sudo arp-scan -l++`	ARP Scan	Scans the local network segment using ARP packets to discover active hosts.