ssh-keygen -t ed25519 -C
ssh-keygen -t ed25519 -C <comment>
Risk: Safe
What it does
Makes a key pair: a padlock (.pub) and its one key.
When to use it
Once per laptop, before your first key login.
Example
$ ssh-keygen -t ed25519 -C "you@laptop"Make ~/.ssh/id_ed25519 and id_ed25519.pub.
$ ssh-keygen -l -f ~/.ssh/id_ed25519.pubShow a key's fingerprint.
$ ssh-keygen -R 10.0.0.5Forget a server's old ID card in known_hosts.
Learn it in: SSH keys · Official docs