uname -a : Displays all system information.
hostnamectl : Shows current hostname and related details.
lscpu : Lists CPU architecture information.
timedatectl status : Shows system time.
ls : Lists files and directories.
touch <filename> : Creates an empty file or updates the last accessed date.
cp <source> <destination> : Copies files from source to destination.
mv <source> <destination> : Moves files or renames them.
rm <filename> : Deletes a file.
top : Displays real-time system processes. htop : An interactive process viewer (needs installation). df -h : Shows disk usage in a human-readable format. free -m : Displays free and used memory in MB. kill : Terminates a process.
pwd : Displays the current directory path.
cd <directory> : Changes the current directory.
mkdir <dirname> : Creates a new directory.
[command] & : Runs command in the background.
jobs : Displays background commands.
fg <command number> : Brings command to the foreground.
chmod [who][+/-][permissions] <file> : Changes file permissions.
chmod u+x <file> : Makes a file executable by its owner.
chown [user]:[group] <file> : Changes file owner and group.
sudo systemctl start <service>: Starts a service.
sudo systemctl stop <service> : Stops a service
sudo systemctl status <service> : Checks the status of a service.
sudo systemctl reload <service> : Reloads a service’s configuration without
interrupting its operation.
journalctl -f : Follows the journal, showing new log messages in real time.
journalctl -u <unit_name> : Displays logs for a specific systemd unit.
crontab -e : Edits cron jobs for the current user.
crontab -l : Lists cron jobs for the current user.
find [directory] -name <search_pattern> : Finds files and directories.
grep <search_pattern> <file> : Searches for a pattern in files.
tar -czvf <name.tar.gz> [files] : Compresses files into a tar.gz archive. tar -xvf <name.tar.[gz|bz|xz]> [destination] : Extracts a compressed tar archive.
nano [file] : Opens a file in the Nano text editor.
cat <file> : Displays the contents of a file.
less <file> : Displays the paginated content of a file.
head <file> : Shows the first few lines of a file.
tail <file> : Shows the last few lines of a file.
awk ‘{print}’ [file] : Prints every line in a file.
sudo apt install <package> : Installs a package.
sudo apt install -f –reinstall <package> : Reinstalls a broken package.
apt search <package> : Searches for APT packages.
apt-cache policy <package> : Lists available package versions.
sudo apt update : Updates package lists.
sudo apt upgrade : Upgrades all upgradable packages.
sudo apt remove <package> : Removes a package.
sudo apt purge <package> : Removes a package and all its configuration files.
ip addr show : Displays network interfaces and IP addresses.
ip -s link : Shows network statistics.
ss -l : Shows listening sockets.
ping <host> : Pings a host and outputs results.
cat /etc/netplan/*.yaml : Displays the current Netplan configuration.
sudo netplan try : Tests a new configuration for a set period of time.
sudo netplan apply : Applies the current Netplan configuration.
snap find <package> : Search for Snap packages.
sudo snap install <snap_name> : Installs a Snap package.
sudo snap remove <snap_name> : Removes a Snap package.
sudo snap refresh : Updates all installed Snap packages.
snap list : Lists all installed Snap packages.
snap info <snap_name> : Displays information about a Snap package.
sudo ufw status : Displays the status of the firewall.
sudo ufw enable : Enables the firewall.
sudo ufw disable : Disables the firewall.
sudo ufw allow <port/service> : Allows traffic on a specific port or service.
sudo ufw deny <port/service> : Denies traffic on a specific port or service.
sudo ufw delete allow/deny <port/service> : Deletes an existing rule.
ssh <user@host> : Connects to a remote host via SSH.
scp <source> <user@host>:<destination> : Securely copies files between hosts.
w : Shows which users are logged in.
sudo adduser <username> : Creates a new user.
sudo deluser <username> : Deletes a user.
sudo passwd <username> : Sets or changes the password for a user.
su <username> : Switches user.
sudo passwd -l <username> : Locks a user account.
sudo passwd -u <username> : Unlocks a user password.
Sudo change <username> : Sets user password expiration date.
sudo ufw status : Displays the status of the firewall.
sudo ufw enable : Enables the firewall.
sudo ufw disable : Disables the firewall.
sudo ufw allow <port/service> : Allows traffic on a specific port or service.
sudo ufw deny <port/service> : Denies traffic on a specific port or service.
sudo ufw delete allow/deny <port/service> : Deletes an existing rule.
id [username] : Displays user and group IDs.
groups [username] : Shows the groups a user belongs to.
sudo addgroup <groupname> : Creates a new group.
sudo delgroup <groupname> : Deletes a group.
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lxd init : initializes LXD before first use
lxc init ubuntu:22.04 <container name> : Creates a lxc system container (without
starting it).
lxc launch ubuntu:24.04 <container name> : Creates and starts a lxc system
container.
lxc launch ubuntu:22.04 <vm name> --vm : Creates and starts a virtual machine.
lxc list : Lists instances.
lxc info <instance> : Shows status information about an instance.
lxc start <instance> : Starts an instance.
lxc stop <instance> [--force] : Stops an instance.
lxc delete <instance> [--force|--interactive] : Deletes an instance.
lxc exec <instance> -- <command> : Runs a command inside an instance.
lxc exec <instance> -- bash : Gets shell access to an instance (if bash is
installed).
lxc console <instance> [flags] : Gets console access to an instance.
lxc file pull <instance>/<instance_filepath> <local_filepath> : Pulls a file from
an instance.
lxc file pull <local_filepath> <instance>/<instance_filepath> : Pushes a file to
an instance.
lxc project create <project> [--config <option>] : Creates a project.
lxc project set <project> <option> : Configures a project.
lxc project switch <project> : Switches to a project.
systemctl --user restart pipewire.service : Restarts the Pipewire service.