SSH(Secure Shell)
An encrypted protocol for securely logging into and managing servers over a network.
SSH is how you remotely control a headless server via the command line. Always disable password login and use SSH keys, change the default port, and consider tools like fail2ban. SSH also powers secure file transfer (SCP/SFTP) and port tunneling.
Key-based authentication is the single most important hardening step: generate a key pair, copy the public key to the server with ssh-copy-id, then disable password authentication entirely so brute-force attempts become pointless. Beyond that, SSH is a versatile tool — SCP and SFTP move files securely, and local or reverse port forwarding lets you tunnel to a service without exposing it publicly. As a rule, never forward SSH straight to the internet without keys and fail2ban; better still, reach it over a VPN so it isn't exposed at all.
Related articles
Port Forwarding
A router rule that directs incoming internet traffic on a specific port to a device on your local network.
Reverse Proxy
A server that sits in front of your services, routing requests by domain name and handling TLS certificates.
VPN(Virtual Private Network)
An encrypted tunnel that lets you securely access your home network from anywhere as if you were local.