sudo不能使用

今天裝完系統發現我的sudo命令不能正常使用，大致情況如下:

 

.......
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.
......

 後來在網上查找了相關資料，具體解決方法如下：

1、用su － 登入root模式

2、改變文件sudoers的權限爲可寫:chmod 740 /etc/sudoers

3、用vi打開sudoers文件:vi /etc/sudoers

4、在root ALL=(ALL) ALL處回車，另起一行寫上：username ALL=(ALL) ALL

5、保存退出

6、把sudoers的權限改爲默認的440:chmod 440 /etc/sudoers

7、退出root到普通用戶模式，使用sudo測試，通過！

注：如果想要在使用sudo時不輸入密碼，可以把4處改爲:

username ALL=NOPASSWD:ALL

 

---

完整樣例：

# /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 specification
root    ALL=(ALL) ALL
#tiger   ALL=(ALL) ALL
tiger   ALL=NOPASSWD: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