在Linux中，我们使用sudo来命令来减少使用root用户的时间，并且提高安全性，下面就简单讲解下如何配置，主要也是记录，怕自己忘了。
系统环境：
[root@master ~]# cat /etc/redhat-release
CentOS Linux release 7.3.1611 (Core)
[root@master ~]# uname -r
3.10.0-514.26.2.el7.x86_64
配置文件路径：/etc/sudoers
[root@master ~]# vim /etc/sudoers（虽然执行visudo也能进入编辑，但还是推荐使用这种）
1 ## Sudoers allows particular users to run various commands as
2 ## the root user, without needing the root password.
3 ##
4 ## Examples are provided at the bottom of the file for collections
5 ## of related commands, which can then be delegated out to particular
6 ## users or groups.
7 ##
8 ## This file must be edited with the 'visudo' command.
9
10 ## Host Aliases
11 ## Groups of machines. You may prefer to use hostnames (perhaps using
12 ## wildcards for entire domains) or IP addresses instead.
13 # Host_Alias FILESERVERS = fs1, fs2
14 # Host_Alias MAILSERVERS = smtp, smtp2
15
16 ## User Aliases
17 ## These aren't often necessary, as you can use regular groups
18 ## (ie, from files, LDAP, NIS, etc) in this file - just use %groupname
19 ## rather than USERALIAS
20 # User_Alias ADMINS = jsmith, mikem
21
22
23 ## Command Aliases
24 ## These are groups of related commands...
25
26 ## Networking
27 # Cmnd_Alias NETWORKING = /sbin/route, /sbin/ifconfig, /bin/ping, /sbin/dhclient, /usr/bin/net, /sbin/iptables, /usr/bin/rfcomm, /usr/bin/wvdial, /sbin/iwconfig, /sbin/mii-tool
28
29 ## Installation and management of software
30 # Cmnd_Alias SOFTWARE = /bin/rpm, /usr/bin/up2date, /usr/bin/yum
31
32 ## Services
33 # Cmnd_Alias SERVICES = /sbin/service, /sbin/chkconfig, /usr/bin/systemctl start, /usr/bin/systemctl stop, /usr/bin/systemctl reload, /usr/bin/systemctl restart, /usr/bin/systemctl status , /usr/bin/systemctl enable, /usr/bin/systemctl disable
34
35 ## Updating the locate database
36 # Cmnd_Alias LOCATE = /usr/bin/updatedb
37
38 ## Storage
39 # Cmnd_Alias STORAGE = /sbin/fdisk, /sbin/sfdisk, /sbin/parted, /sbin/partprobe, /bin/mount, /bin/umount
40
41 ## Delegating permissions
42 # Cmnd_Alias DELEGATING = /usr/sbin/visudo, /bin/chown, /bin/chmod, /bin/chgrp
43
44 ## Processes
45 # Cmnd_Alias PROCESSES = /bin/nice, /bin/kill, /usr/bin/kill, /usr/bin/killall
46
47 ## Drivers
48 # Cmnd_Alias DRIVERS = /sbin/modprobe
49
50 # Defaults specification
51
52 #
53 # Refuse to run if unable to disable echo on the tty.
54 #
55 Defaults !visiblepw
56
57 #
58 # Preserving HOME has security implications since many programs
59 # use it when searching for configuration files. Note that HOME
60 # is already set when the the env_reset option is enabled, so
61 # this option is only effective for configurations where either
62 # env_reset is disabled or HOME is present in the env_keep list.
63 #
64 Defaults always_set_home
65
66 Defaults env_reset
67 Defaults env_keep = "COLORS DISPLAY HOSTNAME HISTSIZE KDEDIR LS_COLORS"
68 Defaults env_keep += "MAIL PS1 PS2 QTDIR USERNAME LANG LC_ADDRESS LC_CTYPE"
69 Defaults env_keep += "LC_COLLATE LC_IDENTIFICATION LC_MEASUREMENT LC_MESSAGES"
70 Defaults env_keep += "LC_MONETARY LC_NAME LC_NUMERIC LC_PAPER LC_TELEPHONE"
71 Defaults env_keep += "LC_TIME LC_ALL LANGUAGE LINGUAS _XKB_CHARSET XAUTHORITY"
72
73 #
74 # Adding HOME to env_keep may enable a user to run unrestricted
75 # commands via sudo.
76 #
77 # Defaults env_keep += "HOME"
78
79 Defaults secure_path = /sbin:/bin:/usr/sbin:/usr/bin
80
81 ## Next comes the main part: which users can run what software on
82 ## which machines (the sudoers file can be shared between multiple
83 ## systems).
84 ## Syntax:
85 ##
86 ## user MACHINE=COMMANDS
87 ##
88 ## The COMMANDS section may have other options added to it.
89 ##
90 ## Allow root to run any commands anywhere
91 root ALL=(ALL) ALL
92 wxh-docker ALL=(root) /usr/bin/systemctl
93
94 ## Allows members of the 'sys' group to run networking, software,
95 ## service management apps and more.
96 # %sys ALL = NETWORKING, SOFTWARE, SERVICES, STORAGE, DELEGATING, PROCESSES, LOCATE, DRIVERS
97
98 ## Allows people in group wheel to run all commands
99 %wheel ALL=(ALL) ALL
100
101 ## Same thing without a password
102 # %wheel ALL=(ALL) NOPASSWD: ALL
103
104 ## Allows members of the users group to mount and unmount the
105 ## cdrom as root
106 # %users ALL=/sbin/mount /mnt/cdrom, /sbin/umount /mnt/cdrom
107
108 ## Allows members of the users group to shutdown this system
109 # %users localhost=/sbin/shutdown -h now
110
111 ## Read drop-in files from /etc/sudoers.d (the # here does not mean a comment)
112 #includedir /etc/sudoers.d
讲解：
其实这个配置文件的核心就是一个命令格式：
用户 来源主机IP/域名=（授权用户） 命令
组 来源主机IP/域名=（授权用户） 命令
以上这些都可以在文件开头定义别名，讲一组用户/IP/命令等整合成一个
91 root ALL=(ALL) ALL
92 wxh-docker ALL=(root) /usr/bin/systemctl
以第91和92行为例，第91行是默认存在的，第92行是我添加的
这行的意思是：允许wxh-docker这个用户在任意位置（不限源IP）连接到这台主机上并且可以以root的身份运行systemctl命令
本文转自1清风揽月1 51CTO博客，原文链接：http://blog.51cto.com/watchmen/1952460，如需转载请自行联系原作者
