[hadoop@localhost ~]$ visudovisudo：/etc/sudoers：權限不夠visudo：/etc/sudoers：權限不夠使用visudo命令打開sudo配置文件## Sudoers allows particular users to run various commands as## the root user, without needing the root password.## 該文件允許特定用戶像root用戶一樣使用各種各樣的命令，而不需要root用戶的密碼#### 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關命令的示例以供選擇，這些示例都可以被特定用戶或## 用戶組所使用 #### This file must be edited with the 'visudo' command.## 該文件必須使用"visudo"命令編輯## Host Aliases## Groups of machines. You may prefer to use hostnames (perhaps using ## wildcards for entire domains) or IP addresses instead.## 對于一組服務器，你可能會更喜歡使用主機名（可能是全域名的通配符）## 、或IP地址，這時可以配置主機別名# 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## 這并不很常用，因為你可以通過使用組來代替一組用戶的別名# User_Alias ADMINS = jsmith, mikem## Command Aliases## These are groups of related commands...## 指定一系列相互關聯的命令（當然可以是一個）的別名，通過賦予該別名sudo權限，## 可以通過sudo調用所有別名包含的命令，下面是一些示例## Networking 網絡操作相關命令別名# 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 軟件安裝管理相關命令別名# Cmnd_Alias SOFTWARE = /bin/rpm, /usr/bin/up2date, /usr/bin/yum## Services 服務相關命令別名# Cmnd_Alias SERVICES = /sbin/service, /sbin/chkconfig## Updating the locate database 本地數據庫升級命令別名# Cmnd_Alias LOCATE = /usr/bin/updatedb## Storage 磁盤操作相關命令別名# Cmnd_Alias STORAGE = /sbin/fdisk, /sbin/sfdisk, /sbin/parted, /sbin/partprobe, /bin/mount, /bin/umount## Delegating permissions 代理權限相關命令別名# Cmnd_Alias DELEGATING = /usr/sbin/visudo, /bin/chown, /bin/chmod, /bin/chgrp## Processes 進程相關命令別名# Cmnd_Alias PROCESSES = /bin/nice, /bin/kill, /usr/bin/kill, /usr/bin/killall## Drivers 驅動命令別名# 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>".# 一些環境變量的相關配置，具體情況可見man soduersDefaults  requirettyDefaults  env_resetDefaults  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).## 下面是規則配置：什么用戶在哪臺服務器上可以執行哪些命令（sudoers文件可以在多個系統上共享）## Syntax(語法):#### user MACHINE=COMMANDS 用戶 登錄的主機=（可以變換的身份） 可以執行的命令#### The COMMANDS section may have other options added to it.## 命令部分可以附帶一些其它的選項#### Allow root to run any commands anywhere ## 允許root用戶執行任意路徑下的任意命令root ALL=(ALL) ALL## Allows members of the 'sys' group to run networking, software, ## service management apps and more.## 允許sys中戶組中的用戶使用NETWORKING等所有別名中配置的命令# %sys ALL = NETWORKING, SOFTWARE, SERVICES, STORAGE, DELEGATING, PROCESSES, LOCATE, DRIVERS## Allows people in group wheel to run all commands## 允許wheel用戶組中的用戶執行所有命令%wheel ALL=(ALL) ALL## Same thing without a password## 允許wheel用戶組中的用戶在不輸入該用戶的密碼的情況下使用所有命令# %wheel ALL=(ALL) NOPASSWD: ALL## Allows members of the users group to mount and unmount the ## cdrom as root## 允許users用戶組中的用戶像root用戶一樣使用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## 允許users用戶組中的用戶關閉localhost這臺服務器# %users localhost=/sbin/shutdown -h now## Read drop-in files from /etc/sudoers.d (the # here does not mean a comment)## 讀取放置在/etc/sudoers.d/文件夾中的文件（此處的#不意味著這是一個聲明）#includedir /etc/sudoers.d