Is it possible to use ssh-copy-id once password based logins are disabled?

Question

Is it possible to use ssh-copy-id once password based logins are disabled? Otherwise, is there an utility for adding an authorized public key to a user or should I edit the ~/.ssh/authorized_keys file manually?

Answer 1

If you have multiple ssh keys and already have one set up for authentication on the server or if you have some other non-password authentication system in place, I believe you can use ssh-copy-id to copy a ssh identity to the server. In the ssh-copy-id manual page it says:

ssh-copy-id is a script that uses ssh to log into a remote machine (presumably using a login password, so password authentication should be enabled, unless you've done some clever use of multiple identities)

ssh-copy-id uses ssh to log into the remote machine, so if you can currently log into the machine, you can use ssh-copy-id. If you can not log into the machine, then you can not use ssh-copy-id. New id's will be appended to ~/.ssh/authorized_keys.