#%PAM-1.0 
auth      required  pam_tally2.so   deny=3lock_time=300 even_deny_root root_unlock_time=10
auth [user_unknown=ignoresuccess=okignoreignore=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    optional     pam_keyinit.so force revoke 
session    required     pam_loginuid.so 
session    include      system-auth 
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 open 

even_deny_root    也限制root用户； 
deny           设置普通用户和root用户连续错误登陆的最大次数，超过最大次数，则锁定该用户 
unlock_time        设定普通用户锁定后，多少时间后解锁，单位是秒； 
root_unlock_time      设定root用户锁定后，多少时间后解锁，单位是秒； 
此处使用的是 pam_tally2 模块，如果不支持 pam_tally2 可以使用 pam_tally 模块。另外，不同的pam版本，设置可能有所不同，具体使用方法，可以参照相关模块的使用规则。

#%PAM-1.0 
auth          required        pam_tally2.so        deny=3unlock_time=300 even_deny_root root_unlock_time=10
auth       include      system-auth 
account    required     pam_nologin.so 
account    include      system-auth 
password   include      system-auth 
session    optional     pam_keyinit.so force revoke 
session    include      system-auth 
session    required     pam_loginuid.so

[root@node100 pam.d]# pam_tally2 --user redhat 
Login           Failures Latest failure     From 
redhat              7    07/16/12 15:18:22  tty1

[root@node100 pam.d]# pam_tally2 -r -u redhat 
Login           Failures Latest failure     From 
redhat              7    07/16/12 15:18:22  tty1