hai , I Wonder if we can do this. I am using Redhat Linux 7.1. I want to authenticate users through RADIUS. Is there any way of using pam_radius_auth.so in such a way PAM looks only in RADIUS database & authenticate the user. The user name should not be present in Linux database. This works. If I have a user say user1 in Linux database (an account in /etc/passwd file) with some password and a same user , user1 in RADIUS database with different password. In some service if I use the line in some service auth sufficient /lib/security/pam_radius_auth.so It works fine. Now I want to authenticate a user who has entry only in RADIUS database & not in Linux database, using the same line. Is it a must that there should be an account for user in /etc/passwd file to get authenticated using RADIUS. Please help me. regards, adharsh.