Delete SSH Keys
Linux Lock An Account
# passwd -l userName
# passwd -l vivekFreeBSD Local An Account
# pw lock userName
# pw local vivekSolaris / HP-UX UNIX Lock An Account
# passwd -l userName
# passwd -l vivekRemove SSH Keys
$HOME/.ssh/ stores all required keys. Simply rename the directory or delete the directory:
# mv /home/vivek/.ssh /home/vivek/nosshlogin
OR
# rm -rf /home/vivek/.ssh
For remote server edit $HOME/.ssh/authorized_keys or $HOME/.ssh/authorized_keys2 file and remove public key. This will delete login from home computer into your server. Finally, you can always delete user from your system using the pw (FreeBSD) or userdel (Linux / UNIX) command.