ssh-keyscan

Get the public SSH keys of remote hosts. More information: https://man.openbsd.org/ssh-keyscan.

• Retrieve all public SSH keys of a remote host:

ssh-keyscan host

• Retrieve all public SSH keys of a remote host listening on a specific port:

ssh-keyscan -p port host

• Retrieve certain types of public SSH keys of a remote host:

ssh-keyscan -t rsa,dsa,ecdsa,ed25519 host

• Manually update the SSH known_hosts file with the fingerprint of a given host:

ssh-keyscan -H host >> ~/.ssh/known_hosts