Linux

#su - oracle
su: incorrect password

#%PAM-1.0
auth       sufficient   /lib/security/$ISA/pam_rootok.so
# Uncomment the following line to implicitly trust users in the "wheel" group.
#auth       sufficient   /lib/security/$ISA/pam_wheel.so trust use_uid
# Uncomment the following line to require a user to be in the "wheel" group.
#auth       required     /lib/security/$ISA/pam_wheel.so use_uid
auth       required     /lib/security/$ISA/pam_stack.so service=system-auth
account    required     /lib/security/$ISA/pam_stack.so service=system-auth
password   required     /lib/security/$ISA/pam_stack.so service=system-auth
# pam_selinux.so close must be first session rule
session    required     /lib/security/$ISA/pam_selinux.so close
session    required     /lib/security/$ISA/pam_stack.so service=system-auth
# pam_selinux.so open and pam_xauth must be last two session rules
session    required     /lib/security/$ISA/pam_selinux.so open
session    optional     /lib/security/$ISA/pam_xauth.so

auth            sufficient      pam_rootok.so
auth            include         system-auth
account         sufficient      pam_succeed_if.so uid = 0 use_uid quiet
account         include         system-auth
password        include         system-auth
session         include         system-auth
session         optional        pam_xauth.so