入门

在一次处理su切换的问的时候出现一个问题, 

[cheng1@localhost ~]$ su cheng2
密码：
su: 鉴定故障
[cheng1@localhost ~]$

试过很多次, 也是这样, 还找了很多文章, 那些哥们说的基本都是加sudo, 当然, 没效果。

后来查着查着发现su有一个wheel组和/etc/pam.d/su, 呃...

先看一下/etc/pam.d/su长什么样子

[root@localhost home]# cat -n /etc/pam.d/su
     1	#%PAM-1.0
     2	auth		sufficient	pam_rootok.so
     3	# Uncomment the following line to implicitly trust users in the "wheel" group.
     4	auth		sufficient	pam_wheel.so trust use_uid
     5	# Uncomment the following line to require a user to be in the "wheel" group.
     6	#auth		required	pam_wheel.so use_uid
     7	auth		substack	system-auth
     8	auth		include		postlogin
     9	account		sufficient	pam_succeed_if.so uid = 0 use_uid quiet
    10	account		include		system-auth
    11	password	include		system-auth
    12	session		include		system-auth
    13	session		include		postlogin
    14	session		optional	pam_xauth.so
[root@localhost home]#

第四行, 这家伙搞的鬼

下面引入Jan哥的一篇文章(非原创):Linux 中的 wheel 组和 staff 组

看了这个一切都明白了

就是服务器限制了su使用权限, 没办法, 也不能直接取消这个配置, 那么就直接把需要su的账号扔进wheel组里面

[root@localhost home]# usermod -G wheel cheng1
[root@localhost home]#

是G不是g, G是追加一个组, 而g是直接修改组, 区别很大

然后就一步达成了

[cheng1@localhost ~]$ su cheng2
[cheng2@localhost cheng1]$

区别出来了

[root@localhost home]# id cheng1 && id cheng2
uid=1002(cheng1) gid=1002(cheng1) 组=1002(cheng1),10(wheel)
uid=1003(cheng2) gid=1003(cheng2) 组=1003(cheng2)