restricting user who can su to root

English Install/Boot/Login
#1

Hello,

Env: OpenSuSE 11.1

I want to restrict users who can su to root by using pam_wheel.so module.
So, I edited /etc/pam.d/su to following.

#%PAM-1.0
auth sufficient pam_rootok.so
auth required pam_wheel.so use_uid
auth include common-auth
account include common-account
password include common-password
session include common-session
session optional pam_xauth.so

But, a user who is not belong to wheel group still can su to root…

Please help!

#2

The simple answer is to change the root password and don’t tell any users - or only those whom you want to be able to use su.

But why would a user need to use su?