Command reference
Most Useful Commands for Servers
Commands for service state, logs, networking, packages, users, disk space, and remote administration.
ssh
Opens a secure remote shell connection.
ssh [options] [user@]host [command]
systemctl
Controls systemd services and system state.
systemctl [command] [unit]
journalctl
Reads the systemd journal.
journalctl [options]
ss
Inspects sockets and listening ports.
ss [options]
ip
Shows and configures networking state.
ip [object] [command]
df
Shows filesystem disk space usage.
df [options] [path]
du
Estimates file and directory space usage.
du [options] [path]
top
Shows live process and resource usage.
top [options]
ps
Reports current processes.
ps [options]
kill
Sends a signal to a process.
kill [signal] PID...
rsync
Synchronizes files locally or over SSH.
rsync [options] source destination
useradd
Creates user accounts.
useradd [options] username
chmod
Changes file mode permissions.
chmod [options] mode file...
chown
Changes file owner and optionally group.
chown [options] owner[:group] file...