Hi, I'm trying to remove any limit on open files for a user; I've set username nofiles to unlimited in /etc/security/logins.conf, but now I get "could not open session" if I try to su to the user. singhh - nofile unlimited I think this is related to PAM, so I've modifed /etc/pam.d/su and /etc/pam.d/login to use pam_limits.so: # cat /etc/pam.d/su #%PAM-1.0 auth sufficient pam_rootok.so # Uncomment the following line to implicitly trust users in the "wheel" group. #auth sufficient pam_wheel.so trust use_uid # Uncomment the following line to require a user to be in the "wheel" group. #auth required pam_wheel.so use_uid auth include system-auth account sufficient pam_succeed_if.so uid = 0 use_uid quiet account include system-auth password include system-auth session required pam_limits.so session include system-auth session optional pam_xauth.so # cat /etc/pam.d/login #%PAM-1.0 auth [user_unknown=ignore success=ok ignore=ignore default=bad] pam_securetty.so auth include system-auth account required pam_nologin.so account include system-auth password include system-auth # pam_selinux.so close should be the first session rule session required pam_selinux.so close session include system-auth session required pam_loginuid.so session optional pam_console.so # pam_selinux.so open should only be followed by sessions to be executed in the user context session required pam_selinux.so pam_limits.so open session optional pam_keyinit.so force revoke What am I doing wrong? S.