I want a production server to push backup files to a backup machine. Backups are being done via
www-data cron script (as they can be edited by website cms), and once it has finished the idea is to send this files to backup server via rsync & ssh.
www-data is a 'no login user' account (no home, no ~/.ssh folder).
In a 'user can login' account I would login, generate a certificate with
ssh-keygen and place public key into
.ssh/authorized_keys in backup machine.
How can I make this 'user no login' account to send files to remote machine with rsync and ssh?