whatis ssh
SSH (Secure Shell)
Also known as: secure shell, sshd, OpenSSH
An encrypted protocol for logging into and running commands on remote machines, also used for file transfer and tunneling.
What Is SSH (Secure Shell) in Linux?
SSH is how almost everyone manages Linux servers. The ssh client connects to the sshd daemon on port 22, authenticates with a key or password, and gives you a remote shell over an encrypted channel.
The same connection can copy files (scp, sftp, rsync), forward ports, and jump through bastion hosts. Per-host settings in ~/.ssh/config save a lot of typing.
Example
ssh -p 2222 alice@server.example.comLearn more about SSH (Secure Shell)
- SSH Beginner's Guide SSH (Secure Shell) lets you log into remote Linux systems, run commands, and transfer files over an encrypted connection. This guide covers key-based authentication, the SSH config file, port forwarding, and common SSH patterns.
- SSH Hardening Guide SSH is the most commonly attacked service on internet-facing Linux servers. This guide covers every important sshd_config setting, key management practices, and tools like fail2ban to reduce your exposure.
- SSH Tunneling Explained: Local, Remote, and Dynamic Port Forwarding SSH can carry more than shells. With -L, -R, and -D it forwards ports through encrypted tunnels, reaching firewalled services, exposing local apps, and acting as a instant SOCKS proxy.
- SCP vs SFTP vs rsync SCP, SFTP, and rsync are the three main tools for transferring files over SSH on Linux. This guide covers when to use each, how they work, and practical command examples for common transfer scenarios.
Related tools
- SSH Config Builder Generate ~/.ssh/config host blocks with keys, jump hosts, and connection keepalives.
- rsync Builder Build rsync sync and backup commands with delete safety, excludes, and SSH transport options.