O "alias" é um script bash e é chamado ssh-copy-id . Verifique as páginas de manual: man ssh-copy-id :
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) It also changes the permissions of the remote user's home,
~/.ssh, and~/.ssh/authorized_keysto remove group writability (which would otherwise prevent you from logging in, if the remotesshdhasStrictModesset in its configuration).