I have a Linux server with about 20 users. They were using
wall command which is annoying. I have root permissions and still want to be able to use it myself. But, how can I restrict normal users from using the Linux
If you want to deny access to for all users, then you might want to remove the setgid bit on
$ ls -l /usr/bin/wall -rwxr-sr-x 1 root tty 13884 2011-08-09 12:15 /usr/bin/wall $ sudo chmod g-s /usr/bin/wall $ echo foo | wall
You should always be able to wall yourself and root should be able to wall everyone, but user A won't be able to broadcast to the rest of the users.