[root@localhost ~]# adduser zhangbiao

[root@localhost ~]# passwd zhangbiao
更改用户 zhangbiao 的密码 。
新的 密码：
无效的密码： 密码未通过字典检查 - 过于简单化/系统化
重新输入新的 密码：
passwd：所有的身份验证令牌已经成功更新。

[root@localhost ~]# sudoers
bash: sudoers: 未找到命令...
[root@localhost ~]# whereis sudoers
sudoers: /etc/sudoers /etc/sudoers.d /usr/libexec/sudoers.so /usr/share/man/man5/sudoers.5.gz

[root@localhost ~]# ls -l /etc/sudoers
-r--r----- 1 root root 4251 9月 25 15:08 /etc/sudoers

[root@localhost ~]# chmod -v u+w /etc/sudoers
mode of "/etc/sudoers" changed from 0440 (r--r-----) to 0640 (rw-r-----)

[root@localhost ~]# vim /etc/sudoers


## Allow root to run any commands anywher 
root ALL=(ALL)  ALL 
zhangbiao ALL=(ALL)  ALL #这个是新增的用户

[root@localhost ~]# chmod -v u-w /etc/sudoers
mode of "/etc/sudoers" changed from 0640 (rw-r-----) to 0440 (r--r-----)

[zhangbiao@localhost ~]$ sudo cat /etc/passwd
[sudo] password for zhangbiao: 

We trust you have received the usual lecture from the local System
Administrator. It usually boils down to these three things:

 #1) Respect the privacy of others.
 #2) Think before you type.
 #3) With great power comes great responsibility.