一、检查本地系统版本

检查本地环境，操作系统版本，本次实践为centos7.6版本。

[root@docker ~]# cat /etc/os-release 
NAME="CentOS Linux"
VERSION="7 (Core)"
ID="centos"
ID_LIKE="rhel fedora"
VERSION_ID="7"
PRETTY_NAME="CentOS Linux 7 (Core)"
ANSI_COLOR="0;31"
CPE_NAME="cpe:/o:centos:centos:7"
HOME_URL="https://www.centos.org/"
BUG_REPORT_URL="https://bugs.centos.org/"

CENTOS_MANTISBT_PROJECT="CentOS-7"
CENTOS_MANTISBT_PROJECT_VERSION="7"
REDHAT_SUPPORT_PRODUCT="centos"
REDHAT_SUPPORT_PRODUCT_VERSION="7"

二、创建redhat普通用户

1.创建redhat用户

[root@docker ~]# useradd redhat

2.为redhat用户设置密码

[root@docker ~]# passwd redhat
Changing password for user redhat.
New password: 
BAD PASSWORD: The password is shorter than 8 characters
Retype new password: 
passwd: all authentication tokens updated successfully.

3.查询创建用户相关命令的绝对路径

[root@docker ~]# which useradd 
/usr/sbin/useradd
[root@docker ~]# which passwd 
/usr/bin/passwd
[root@docker ~]# which userdel 
/usr/sbin/userdel

三、编辑/etc/sudoers文件

[root@docker ~]# vim /etc/sudoers
[root@docker ~]# grep redhat /etc/sudoers
redhat  ALL=(ALL)      /usr/sbin/useradd,/usr/bin/passwd,/usr/sbin/userdel

四、检查redhat用户权限

1.切换到redhat用户

[root@docker ~]# su -  redhat
[redhat@docker ~]$ 

2.新建huawei账号

[redhat@docker ~]$ sudo useradd huawei

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.

[sudo] password for redhat: 

3.查看新创建用户

[redhat@docker ~]$ id huawei
uid=1002(huawei) gid=1002(huawei) groups=1002(huawei)

4.为huawei账号设置密码

[redhat@docker ~]$ sudo passwd huawei
Changing password for user huawei.
New password: 
BAD PASSWORD: The password is shorter than 8 characters
Retype new password: 
passwd: all authentication tokens updated successfully.

5.删除huawei账号

[redhat@docker ~]$ sudo userdel huawei
[redhat@docker ~]$ id huawei
id: huawei: no such user

五、批量用户授权

1.设置别名

[root@docker ~]# grep -Evn '^#|^$|^##'  /etc/sudoers
22:User_Alias ADMINS = zhangsan, lisi
30:Cmnd_Alias USERTEST =  /usr/sbin/useradd, /usr/bin/passwd, /usr/sbin/userdel 
59:Defaults   !visiblepw
68:Defaults    always_set_home
69:Defaults    match_group_by_gid
77:Defaults    always_query_group_plugin
79:Defaults    env_reset
80:Defaults    env_keep =  "COLORS DISPLAY HOSTNAME HISTSIZE KDEDIR LS_COLORS"
81:Defaults    env_keep += "MAIL PS1 PS2 QTDIR USERNAME LANG LC_ADDRESS LC_CTYPE"
82:Defaults    env_keep += "LC_COLLATE LC_IDENTIFICATION LC_MEASUREMENT LC_MESSAGES"
83:Defaults    env_keep += "LC_MONETARY LC_NAME LC_NUMERIC LC_PAPER LC_TELEPHONE"
84:Defaults    env_keep += "LC_TIME LC_ALL LANGUAGE LINGUAS _XKB_CHARSET XAUTHORITY"
92:Defaults    secure_path = /sbin:/bin:/usr/sbin:/usr/bin
104:root    ALL=(ALL)     ALL
105:redhat  ALL=(ALL)      /usr/sbin/useradd,/usr/bin/passwd,/usr/sbin/userdel
112:%wheel    ALL=(ALL)    ALL

2.配置sudo授权

[root@docker ~]# grep ADMINS /etc/sudoers
# User_Alias ADMINS = jsmith, mikem
User_Alias ADMINS = zhangsan, lisi
ADMINS  ALL=(ALL)    USERTEST

六、测试批量授权效果

1.新建用户zhangsan

[root@docker ~]# useradd zhangsan
[root@docker ~]# passwd zhangsan
Changing password for user zhangsan.
New password: 
BAD PASSWORD: The password contains the user name in some form
Retype new password: 
passwd: all authentication tokens updated successfully.

2.切换zhangsan用户

[root@docker ~]# su - zhangsan

3.新建lisi用户并设置密码

[zhangsan@docker ~]$ sudo useradd lisi

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.

[sudo] password for zhangsan: 
[zhangsan@docker ~]$ sudo passwd lisi
Changing password for user lisi.
New password: 
BAD PASSWORD: The password is shorter than 8 characters
Retype new password: 
passwd: all authentication tokens updated successfully.

4.切换lisi用户

[zhangsan@docker ~]$ su - lisi
Password: 
[lisi@docker ~]$ id lisi
uid=1003(lisi) gid=1003(lisi) groups=1003(lisi)

5.切换lisi用户

[zhangsan@docker ~]$ su - lisi
Password: 
[lisi@docker ~]$ id lisi
uid=1003(lisi) gid=1003(lisi) groups=1003(lisi)

6.测试lisi用户权限

[lisi@docker ~]$ sudo useradd user

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.

[sudo] password for lisi: 
[lisi@docker ~]$ sudo passwd user
Changing password for user user.
New password: 
BAD PASSWORD: The password is shorter than 8 characters
Retype new password: 
passwd: all authentication tokens updated successfully.
[lisi@docker ~]$ id user
uid=1004(user) gid=1004(user) groups=1004(user)
[lisi@docker ~]$ sudo userdel user
[lisi@docker ~]$ id user
id: user: no such user