How to copy SSH public key to server

Mostly used for passwordless SSH login; there are a few methods to copy your SSH public key to the SSH server.

1. Use SSH‘s bundled command, ssh-copy-id

   $ ssh-copy-id user@host

   If you want to use other public key rather that then one in the default location,
   use the -i option as the following

   $ ssh-copy-id -i ~/.ssh/other_key.pub username@host

2. Manually append the content of your public key file (normally ~/.ssh/id_rsa.pub to the server’s ~/.ssh/authorized_keys
3. Using the following simple Bash script

   $ cat ~/.ssh/id_rsa.pub | ssh user@host 'cat >> ~/.ssh/authorized_keys