linux命令-visudo


sudo的工作过程如下:

1,当用户执行sudo时,系统会主动寻找/etc/sudoers文件,判断该用户是否有执行sudo的权限

2,确认用户具有可执行sudo的权限后,让用户输入用户自己的密码确认

3,若密码输入成功,则开始执行sudo后续的命令

4,root执行sudo时不需要输入密码(eudoers文件中有配置root ALL=(ALL) ALL这样一条规则)

5,若欲切换的身份与执行者的身份相同,也不需要输入密码

 

visudo使用vi打开/etc/sudoers文件,但是在保存退出时,visudo会检查内部语法,避免用户输入错误信息

visudo需要root权限

  1. [hadoop@localhost ~]$ visudo  
  2. visudo:/etc/sudoers:权限不够  
  3. visudo:/etc/sudoers:权限不够  
[hadoop@localhost ~]$ visudo
visudo:/etc/sudoers:权限不够
visudo:/etc/sudoers:权限不够

使用visudo命令打开sudo配置文件

## Sudoers allows particular users to run various commands as  
## the root user, without needing the root password.  
## 该文件允许特定用户像root用户一样使用各种各样的命令,而不需要root用户的密码  
##  
## Examples are provided at the bottom of the file for collections  
## of related commands, which can then be delegated out to particular  
## users or groups.  
## 在文件的底部提供了很多相关命令的示例以供选择,这些示例都可以被特定用户或  
## 用户组所使用   
##  
## This file must be edited with the 'visudo' command.  
## 该文件必须使用"visudo"命令编辑  
  
## Host Aliases  
## Groups of machines. You may prefer to use hostnames (perhaps using   
## wildcards for entire domains) or IP addresses instead.  
## 对于一组服务器,你可能会更喜欢使用主机名(可能是全域名的通配符)  
## 、或IP地址,这时可以配置主机别名  
# Host_Alias     FILESERVERS = fs1, fs2  
# Host_Alias     MAILSERVERS = smtp, smtp2  
  
## User Aliases  
## These aren't often necessary, as you can use regular groups  
## (ie, from files, LDAP, NIS, etc) in this file - just use %groupname   
## rather than USERALIAS  
## 这并不很常用,因为你可以通过使用组来代替一组用户的别名  
# User_Alias ADMINS = jsmith, mikem  
  
## Command Aliases  
## These are groups of related commands...  
## 指定一系列相互关联的命令(当然可以是一个)的别名,通过赋予该别名sudo权限,  
## 可以通过sudo调用所有别名包含的命令,下面是一些示例  
  
## Networking 网络操作相关命令别名  
# 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  
  
## Installation and management of software 软件安装管理相关命令别名  
# Cmnd_Alias SOFTWARE = /bin/rpm, /usr/bin/up2date, /usr/bin/yum  
  
## Services 服务相关命令别名  
# Cmnd_Alias SERVICES = /sbin/service, /sbin/chkconfig  
  
## Updating the locate database 本地数据库升级命令别名  
# Cmnd_Alias LOCATE = /usr/bin/updatedb  
  
## Storage 磁盘操作相关命令别名  
# Cmnd_Alias STORAGE = /sbin/fdisk, /sbin/sfdisk, /sbin/parted, /sbin/partprobe  
, /bin/mount, /bin/umount  
  
## Delegating permissions 代理权限相关命令别名  
# Cmnd_Alias DELEGATING = /usr/sbin/visudo, /bin/chown, /bin/chmod, /bin/chgrp   
  
## Processes 进程相关命令别名  
# Cmnd_Alias PROCESSES = /bin/nice, /bin/kill, /usr/bin/kill, /usr/bin/killall  
  
## Drivers 驱动命令别名  
# Cmnd_Alias DRIVERS = /sbin/modprobe  
  
# Defaults specification  
  
#  
# Disable "ssh hostname sudo <cmd>", because it will show the password in clear.   
#         You have to run "ssh -t hostname sudo <cmd>".  
# 一些环境变量的相关配置,具体情况可见man soduers  
Defaults    requiretty  
  
Defaults    env_reset  
Defaults    env_keep =  "COLORS DISPLAY HOSTNAME HISTSIZE INPUTRC KDEDIR LS_COLORS"  
Defaults    env_keep += "MAIL PS1 PS2 QTDIR USERNAME LANG LC_ADDRESS LC_CTYPE"  
Defaults    env_keep += "LC_COLLATE LC_IDENTIFICATION LC_MEASUREMENT LC_MESSAGES"  
Defaults    env_keep += "LC_MONETARY LC_NAME LC_NUMERIC LC_PAPER LC_TELEPHONE"  
Defaults    env_keep += "LC_TIME LC_ALL LANGUAGE LINGUAS _XKB_CHARSET XAUTHORITY"  
  
Defaults    secure_path = /sbin:/bin:/usr/sbin:/usr/bin  
  
## Next comes the main part: which users can run what software on   
## which machines (the sudoers file can be shared between multiple  
## systems).  
## 下面是规则配置:什么用户在哪台服务器上可以执行哪些命令(sudoers文件可以在多个系统上共享)  
## Syntax(语法):  
##  
##  user    MACHINE=COMMANDS 用户 登录的主机=(可以变换的身份) 可以执行的命令  
##  
## The COMMANDS section may have other options added to it.  
## 命令部分可以附带一些其它的选项  
##  
## Allow root to run any commands anywhere   
## 允许root用户执行任意路径下的任意命令  
root    ALL=(ALL)   ALL  
  
## Allows members of the 'sys' group to run networking, software,   
## service management apps and more.  
## 允许sys中户组中的用户使用NETWORKING等所有别名中配置的命令  
# %sys ALL = NETWORKING, SOFTWARE, SERVICES, STORAGE, DELEGATING, PROCESSES, LOCATE  
, DRIVERS  
  
## Allows people in group wheel to run all commands  
## 允许wheel用户组中的用户执行所有命令  
%wheel  ALL=(ALL)   ALL  
  
## Same thing without a password  
## 允许wheel用户组中的用户在不输入该用户的密码的情况下使用所有命令  
# %wheel    ALL=(ALL)   NOPASSWD: ALL  
  
## Allows members of the users group to mount and unmount the   
## cdrom as root  
## 允许users用户组中的用户像root用户一样使用mount、unmount、chrom命令  
# %users  ALL=/sbin/mount /mnt/cdrom, /sbin/umount /mnt/cdrom  
  
## Allows members of the users group to shutdown this system  
## 允许users用户组中的用户关闭localhost这台服务器  
# %users  localhost=/sbin/shutdown -h now  
  
## Read drop-in files from /etc/sudoers.d (the # here does not mean a comment)  
## 读取放置在/etc/sudoers.d/文件夹中的文件(此处的#不意味着这是一个声明)  
#includedir /etc/sudoers.d  
## Sudoers allows particular users to run various commands as
## the root user, without needing the root password.
## 该文件允许特定用户像root用户一样使用各种各样的命令,而不需要root用户的密码
##
## Examples are provided at the bottom of the file for collections
## of related commands, which can then be delegated out to particular
## users or groups.
## 在文件的底部提供了很多相关命令的示例以供选择,这些示例都可以被特定用户或
## 用户组所使用 
##
## This file must be edited with the 'visudo' command.
## 该文件必须使用"visudo"命令编辑

## Host Aliases
## Groups of machines. You may prefer to use hostnames (perhaps using 
## wildcards for entire domains) or IP addresses instead.
## 对于一组服务器,你可能会更喜欢使用主机名(可能是全域名的通配符)
## 、或IP地址,这时可以配置主机别名
# Host_Alias     FILESERVERS = fs1, fs2
# Host_Alias     MAILSERVERS = smtp, smtp2

## User Aliases
## These aren't often necessary, as you can use regular groups
## (ie, from files, LDAP, NIS, etc) in this file - just use %groupname 
## rather than USERALIAS
## 这并不很常用,因为你可以通过使用组来代替一组用户的别名
# User_Alias ADMINS = jsmith, mikem

## Command Aliases
## These are groups of related commands...
## 指定一系列相互关联的命令(当然可以是一个)的别名,通过赋予该别名sudo权限,
## 可以通过sudo调用所有别名包含的命令,下面是一些示例

## Networking 网络操作相关命令别名
# 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

## Installation and management of software 软件安装管理相关命令别名
# Cmnd_Alias SOFTWARE = /bin/rpm, /usr/bin/up2date, /usr/bin/yum

## Services 服务相关命令别名
# Cmnd_Alias SERVICES = /sbin/service, /sbin/chkconfig

## Updating the locate database 本地数据库升级命令别名
# Cmnd_Alias LOCATE = /usr/bin/updatedb

## Storage 磁盘操作相关命令别名
# Cmnd_Alias STORAGE = /sbin/fdisk, /sbin/sfdisk, /sbin/parted, /sbin/partprobe
, /bin/mount, /bin/umount

## Delegating permissions 代理权限相关命令别名
# Cmnd_Alias DELEGATING = /usr/sbin/visudo, /bin/chown, /bin/chmod, /bin/chgrp 

## Processes 进程相关命令别名
# Cmnd_Alias PROCESSES = /bin/nice, /bin/kill, /usr/bin/kill, /usr/bin/killall

## Drivers 驱动命令别名
# Cmnd_Alias DRIVERS = /sbin/modprobe

# Defaults specification

#
# Disable "ssh hostname sudo <cmd>", because it will show the password in clear. 
#         You have to run "ssh -t hostname sudo <cmd>".
# 一些环境变量的相关配置,具体情况可见man soduers
Defaults    requiretty

Defaults    env_reset
Defaults    env_keep =  "COLORS DISPLAY HOSTNAME HISTSIZE INPUTRC KDEDIR LS_COLORS"
Defaults    env_keep += "MAIL PS1 PS2 QTDIR USERNAME LANG LC_ADDRESS LC_CTYPE"
Defaults    env_keep += "LC_COLLATE LC_IDENTIFICATION LC_MEASUREMENT LC_MESSAGES"
Defaults    env_keep += "LC_MONETARY LC_NAME LC_NUMERIC LC_PAPER LC_TELEPHONE"
Defaults    env_keep += "LC_TIME LC_ALL LANGUAGE LINGUAS _XKB_CHARSET XAUTHORITY"

Defaults    secure_path = /sbin:/bin:/usr/sbin:/usr/bin

## Next comes the main part: which users can run what software on 
## which machines (the sudoers file can be shared between multiple
## systems).
## 下面是规则配置:什么用户在哪台服务器上可以执行哪些命令(sudoers文件可以在多个系统上共享)
## Syntax(语法):
##
## 	user	MACHINE=COMMANDS 用户 登录的主机=(可以变换的身份) 可以执行的命令
##
## The COMMANDS section may have other options added to it.
## 命令部分可以附带一些其它的选项
##
## Allow root to run any commands anywhere 
## 允许root用户执行任意路径下的任意命令
##账户名  主机名称=(可切换的身份)  可用的指令 root ALL=(ALL) ALL ## Allows members of the 'sys' group to run networking, software, ## service management apps and more. ## 允许sys中户组中的用户使用NETWORKING等所有别名中配置的命令 # %sys ALL = NETWORKING, SOFTWARE, SERVICES, STORAGE, DELEGATING, PROCESSES, LOCATE , DRIVERS ## Allows people in group wheel to run all commands ## 允许wheel用户组中的用户执行所有命令 %wheel ALL=(ALL) ALL ## Same thing without a password ## 允许wheel用户组中的用户在不输入该用户的密码的情况下使用所有命令 # %wheel ALL=(ALL) NOPASSWD: ALL ## Allows members of the users group to mount and unmount the ## cdrom as root ## 允许users用户组中的用户像root用户一样使用mount、unmount、chrom命令 # %users ALL=/sbin/mount /mnt/cdrom, /sbin/umount /mnt/cdrom ## Allows members of the users group to shutdown this system ## 允许users用户组中的用户关闭localhost这台服务器 # %users localhost=/sbin/shutdown -h now ## Read drop-in files from /etc/sudoers.d (the # here does not mean a comment) ## 读取放置在/etc/sudoers.d/文件夹中的文件(此处的#不意味着这是一个声明) #includedir /etc/sudoers.d

  

特别要注意的是别名一定要使用大写

原文自:Linux用户配置sudo权限(visudo)

 
 
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posted @ 2015-12-01 15:26  超超xc  Views(2413)  Comments(0Edit  收藏  举报
I suppose,were childrenonec.