i'd somehow gotten locked out of 2 of my oracle free servers
/etc/sudoers
/etc/pam.d/sshd
/etc/pam.d/sudo
/etc/pam.d/sudo-i
had been deleted, i've now regained access by copying the contents of those files from a different server
these servers are set up to use key-only authentication and only 1 user is allowed over ssh
this is possibly due to an automated intrusion, a botnet maybe, will keep this updated
