Hi again, No, it wasn't the issue. But I found the problem already. All I needed to do was changing %oneadmin into oneadmin. So my sudoers file looks like this now: Cmnd_Alias ONECMD = /usr/sbin/xm, /usr/sbin/xentop oneadmin ALL=(ALL) NOPASSWD: ONECMD Thanks for your help. Regards, Maciej