SSH Keys and Hardening

SSH is the normal way to administer a VPS. Key-based login is safer than password login because the private key stays on your machine.

ssh-keygen -t ed25519 -C "[email protected]"
ssh user@server-ip

Hardening usually means editing /etc/ssh/sshd_config:

PasswordAuthentication no
PermitRootLogin no

Then reload SSH:

sudo systemctl reload ssh

Further Learning

• “OpenSSH authorized_keys” — key-based auth
• “sshd_config PasswordAuthentication” — disabling password login
• “SSH hardening VPS” — practical security baseline

SSH Keys and Hardening

SSH is how you remotely log into and control a server. Logging in with a key (instead of a password) is much safer — the secret half of the key never leaves your own computer.

Setting up key-based login

ssh-keygen -t ed25519 -C "[email protected]"   # generate a key pair on your machine
ssh user@server-ip                            # connect using it

You get a public key (safe to share, goes on the server) and a private key (stays secret, on your machine only).

Locking the door behind you

Once key-based login works, you can turn off password login entirely — so even a guessed/leaked password can’t get anyone in. Edit /etc/ssh/sshd_config:

PasswordAuthentication no
PermitRootLogin no

Then apply the change:

sudo systemctl reload ssh

The one rule that saves you from disaster

In one sentence

SSH keys are safer than passwords for logging into a server — generate a key pair, add the public half to the server, then disable password/root login entirely, but always test a second session before closing your first to avoid locking yourself out.

Want to go deeper?

Switch to Expert mode above for the full authorized_keys setup and hardening checklist.