Ubuntu 更改源

1.可選  備份

   cp     /etc/apt/sources.list      /etc/apt/sources.list.backup

2.修改更新源

       vi /etc/apt/sources.list

3.替換其中內容

       

ubuntu.cn99.com源（推薦）:

deb http://ubuntu.cn99.com/ubuntu/ precise main restricted universe multiverse
deb http://ubuntu.cn99.com/ubuntu/ precise-updates main restricted universe multiverse
deb http://ubuntu.cn99.com/ubuntu/ precise-security main restricted universe multiverse
deb http://ubuntu.cn99.com/ubuntu/ precise-backports main restricted universe multiverse
deb http://ubuntu.cn99.com/ubuntu-cn/ precise main restricted universe multiverse

4.更新源

           apt-get update