sudo的配置文件是/etc/sudoers,visudo修改时会锁住sudoers文件,保存修改到临时文件,然后检查文件格式,确保正确后才会覆盖sudoers文件. 必须保证sudoers格式正确,否则sudo将无法运行.

/etc/sudoers

# /etc/sudoers## This file MUST be edited with the 'visudo' command as root.## See the man page for details on how to write a sudoers file.#Defaults        env_reset# Host alias specification# User alias specification# Cmnd alias specification# User privilege specificationroot    ALL=(ALL) ALL# Uncomment to allow members of group sudo to not need a password# (Note that later entries override this, so you might need to move# it further down)%sudo ALL=NOPASSWD: ALL

sudo group

neo@debian:/etc/mysql$ cat /etc/group | grep 'sudo'sudo:x:27:neo

visudo调用的默认编辑器是vi,如果要临时使用其他编辑器,在该命令前加上EDITOR环境变量即可.

[root@netkiller ~]# EDITOR=vim visudo

>1 允许neo用户从任何主机登录,以root的身份执行/usr/sbin/useradd命令neo   ALL=(root) /usr/sbin/useradd >2 允许jam用户从任何主机登录,以root的身份无密码使用sudo执行/sbin/iptables -n -t filter -L jam   ALL=(ALL) NOPASSWD: /sbin/iptables -n -t filter -L >3 neo用户从任何主机登录,以root的身份执行自定义命令链里面的命令Cmnd_Alias USERCOMMAND = /sbin/route,/sbin/ifconfig,/bin/ping,/sbin/dhclient,/usr/bin/net,/sbin/iptables,/usr/bin/rfcomm,/usr/bin/wvdial,/sbin/iwconfigneo   ALL=(root)    USERCOMMAND

ubuntu NOPASSWD sudo的时候不需要输入密码

组

%admin ALL=(ALL)ALL改为%admin ALL=(ALL) NOPASSWD: NOPASSWD: ALL

用户

www localhost=NOPASSWD: /bin/cat, /bin/ls

命令前面加‘!’可以禁止用户运行该命令

neo ALL = （root） /bin/mount, /bin/umount, !/bin/mount /data0dba ALL = /bin/mount /u0[1-5], /bin/umount /u0[1-5]

Cmnd_Alias 定义命令别名

Cmnd_Alias WEBMASTER = /srv/nginx/sbin/nginx, /srv/php/sbin/php-fpm, !/srv/mysql/bin/mysqlwww localhost = NETWORKING, SERVICES, DELEGATING, PROCESSES, WEBMASTER

自定义用户组(以所有的身份)执行自定义的命令链里的命令

Cmnd_Alias USERCOMMAND = /sbin/route,/sbin/ifconfig,/bin/ping,/usr/sbin/mtr,/bin/traceroute,/usr/bin/top,/bin/df,/usr/bin/free,/usr/bin/du,/bin/ls,/bin/date,/usr/bin/lessUser_Alias    ADMINS = user1, user2ADMINS	ALL=(ALL)	USERCOMMAND

## Allow root to run any commands anywhereroot    ALL=(ALL)       ALLneo     ALL=(ALL)       ALL%wheel  ALL=(ALL)       ALL

1 修改sudo记录密码的时间Defaults:用户名 timestamp_timeout=20eg:Defaults:redhat timestamp_timeout=202 默认sudo命令只能在tty上执行,注释掉下面选项可以使程序调用sudo命令Defaults    requiretty