Ubuntu 12.04更新源

1、首先备份Ubuntu12.04源列表

sudo cp /etc/apt/sources.list /etc/apt/sources.list.backup （备份下当前的源列表）

2、修改更新源

sudo gedit /etc/apt/sources.list （打开Ubuntu 12.04源列表文件）

3、把里面的列表替换成下面的列表

163源

deb http://mirrors.163.com/ubuntu/ precise main restricted
deb-src http://mirrors.163.com/ubuntu/ precise main restricted
deb http://mirrors.163.com/ubuntu/ precise-updates main restricted
deb-src http://mirrors.163.com/ubuntu/ precise-updates main restricted
deb http://mirrors.163.com/ubuntu/ precise universe
deb-src http://mirrors.163.com/ubuntu/ precise universe
deb http://mirrors.163.com/ubuntu/ precise-updates universe
deb-src http://mirrors.163.com/ubuntu/ precise-updates universe
deb http://mirrors.163.com/ubuntu/ precise multiverse
deb-src http://mirrors.163.com/ubuntu/ precise multiverse
deb http://mirrors.163.com/ubuntu/ precise-updates multiverse
deb-src http://mirrors.163.com/ubuntu/ precise-updates multiverse
deb http://mirrors.163.com/ubuntu/ precise-backports main restricted universe multiverse
deb-src http://mirrors.163.com/ubuntu/ precise-backports main restricted universe multiverse
deb http://mirrors.163.com/ubuntu/ precise-security main restricted
deb-src http://mirrors.163.com/ubuntu/ precise-security main restricted
deb http://mirrors.163.com/ubuntu/ precise-security universe
deb-src http://mirrors.163.com/ubuntu/ precise-security universe
deb http://mirrors.163.com/ubuntu/ precise-security multiverse
deb-src http://mirrors.163.com/ubuntu/ precise-security multiverse
deb http://extras.ubuntu.com/ubuntu precise main
deb-src http://extras.ubuntu.com/ubuntu precise main

aliyun源

deb http://mirrors.aliyun.com/debian wheezy main contrib non-free  
deb-src http://mirrors.aliyun.com/debian wheezy main contrib non-free  
deb http://mirrors.aliyun.com/debian wheezy-updates main contrib non-free  
deb-src http://mirrors.aliyun.com/debian wheezy-updates main contrib non-free  
deb http://mirrors.aliyun.com/debian-security wheezy/updates main contrib non-free  
deb-src http://mirrors.aliyun.com/debian-security wheezy/updates main contrib non-free 

sohu源

deb http://mirrors.sohu.com/ubuntu/ precise main restricted
deb-src http://mirrors.sohu.com/ubuntu/ precise main restricted
deb http://mirrors.sohu.com/ubuntu/ precise-updates main restricted
deb-src http://mirrors.sohu.com/ubuntu/ precise-updates main restricted
deb http://mirrors.sohu.com/ubuntu/ precise universe
deb-src http://mirrors.sohu.com/ubuntu/ precise universe
deb http://mirrors.sohu.com/ubuntu/ precise-updates universe
deb-src http://mirrors.sohu.com/ubuntu/ precise-updates universe
deb http://mirrors.sohu.com/ubuntu/ precise multiverse
deb-src http://mirrors.sohu.com/ubuntu/ precise multiverse
deb http://mirrors.sohu.com/ubuntu/ precise-updates multiverse
deb-src http://mirrors.sohu.com/ubuntu/ precise-updates multiverse
deb http://mirrors.sohu.com/ubuntu/ precise-backports main restricted universe multiverse
deb-src http://mirrors.sohu.com/ubuntu/ precise-backports main restricted universe multiverse
deb http://mirrors.sohu.com/ubuntu/ precise-security main restricted
deb-src http://mirrors.sohu.com/ubuntu/ precise-security main restricted
deb http://mirrors.sohu.com/ubuntu/ precise-security universe
deb-src http://mirrors.sohu.com/ubuntu/ precise-security universe
deb http://mirrors.sohu.com/ubuntu/ precise-security multiverse
deb-src http://mirrors.sohu.com/ubuntu/ precise-security multiverse
deb http://extras.ubuntu.com/ubuntu precise main
deb-src http://extras.ubuntu.com/ubuntu precise main

ubuntu.cn99.com源（推荐）:

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

教育网源
如果你是在校大学生，可以使用校园网/教育网，就是用教育网的资源吧，尤其是支持ipv6的，那更新速度就按兆算了。

电子科技大学

deb http://ubuntu.uestc.edu.cn/ubuntu/ precise main restricted universe multiverse
deb http://ubuntu.uestc.edu.cn/ubuntu/ precise-backports main restricted universe multiverse
deb http://ubuntu.uestc.edu.cn/ubuntu/ precise-proposed main restricted universe multiverse
deb http://ubuntu.uestc.edu.cn/ubuntu/ precise-security main restricted universe multiverse
deb http://ubuntu.uestc.edu.cn/ubuntu/ precise-updates main restricted universe multiverse
deb-src http://ubuntu.uestc.edu.cn/ubuntu/ precise main restricted universe multiverse
deb-src http://ubuntu.uestc.edu.cn/ubuntu/ precise-backports main restricted universe multiverse
deb-src http://ubuntu.uestc.edu.cn/ubuntu/ precise-proposed main restricted universe multiverse
deb-src http://ubuntu.uestc.edu.cn/ubuntu/ precise-security main restricted universe multiverse
deb-src http://ubuntu.uestc.edu.cn/ubuntu/ precise-updates main restricted universe multiverse

中国科技大学

deb http://debian.ustc.edu.cn/ubuntu/ precise main restricted universe multiverse
deb http://debian.ustc.edu.cn/ubuntu/ precise-backports restricted universe multiverse
deb http://debian.ustc.edu.cn/ubuntu/ precise-proposed main restricted universe multiverse
deb http://debian.ustc.edu.cn/ubuntu/ precise-security main restricted universe multiverse
deb http://debian.ustc.edu.cn/ubuntu/ precise-updates main restricted universe multiverse
deb-src http://debian.ustc.edu.cn/ubuntu/ precise main restricted universe multiverse
deb-src http://debian.ustc.edu.cn/ubuntu/ precise-backports main restricted universe multiverse
deb-src http://debian.ustc.edu.cn/ubuntu/ precise-proposed main restricted universe multiverse
deb-src http://debian.ustc.edu.cn/ubuntu/ precise-security main restricted universe multiverse
deb-src http://debian.ustc.edu.cn/ubuntu/ precise-updates main restricted universe multiverse

北京理工大学

deb http://mirror.bjtu.edu.cn/ubuntu/ precise main multiverse restricted universe
deb http://mirror.bjtu.edu.cn/ubuntu/ precise-backports main multiverse restricted universe
deb http://mirror.bjtu.edu.cn/ubuntu/ precise-proposed main multiverse restricted universe
deb http://mirror.bjtu.edu.cn/ubuntu/ precise-security main multiverse restricted universe
deb http://mirror.bjtu.edu.cn/ubuntu/ precise-updates main multiverse restricted universe
deb-src http://mirror.bjtu.edu.cn/ubuntu/ precise main multiverse restricted universe
deb-src http://mirror.bjtu.edu.cn/ubuntu/ precise-backports main multiverse restricted universe
deb-src http://mirror.bjtu.edu.cn/ubuntu/ precise-proposed main multiverse restricted universe
deb-src http://mirror.bjtu.edu.cn/ubuntu/ precise-security main multiverse restricted universe
deb-src http://mirror.bjtu.edu.cn/ubuntu/ precise-updates main multiverse restricted universe

官方源

deb http://old-releases.ubuntu.com/ubuntu lucid main restricted universe multiverse   
deb http://old-releases.ubuntu.com/ubuntu lucid-security main restricted universe multiverse   
deb http://old-releases.ubuntu.com/ubuntu lucid-updates main restricted universe multiverse   
deb http://old-releases.ubuntu.com/ubuntu lucid-proposed main restricted universe multiverse   
deb http://old-releases.ubuntu.com/ubuntu lucid-backports main restricted universe multiverse    
deb-src http://old-releases.ubuntu.com/ubuntu lucid main restricted universe multiverse   
deb-src http://old-releases.ubuntu.com/ubuntu lucid-security main restricted universe multiverse   
deb-src http://old-releases.ubuntu.com/ubuntu lucid-updates main restricted universe multiverse   
deb-src http://old-releases.ubuntu.com/ubuntu lucid-proposed main restricted universe multiverse   
deb-src http://old-releases.ubuntu.com/ubuntu lucid-backports main restricted universe multiverse  

官方源

###### Ubuntu Main Repos
 
deb http://old-releases.ubuntu.com/ubuntu/ lucid main restricted
deb-src http://old-releases.ubuntu.com/ubuntu/ lucid main restricted

官方源【Ubuntu10.04亲测可用】

deb http://old-releases.ubuntu.com/ubuntu lucid main restricted universe multiverse    

deb http://old-releases.ubuntu.com/ubuntu lucid-security main restricted universe multiverse    

deb http://old-releases.ubuntu.com/ubuntu lucid-updates main restricted universe multiverse    

deb http://old-releases.ubuntu.com/ubuntu lucid-proposed main restricted universe multiverse    

deb http://old-releases.ubuntu.com/ubuntu lucid-backports main restricted universe multiverse    

deb-src http://old-releases.ubuntu.com/ubuntu lucid main restricted universe multiverse    

deb-src http://old-releases.ubuntu.com/ubuntu lucid-security main restricted universe multiverse    

deb-src http://old-releases.ubuntu.com/ubuntu lucid-updates main restricted universe multiverse    

deb-src http://old-releases.ubuntu.com/ubuntu lucid-proposed main restricted universe multiverse    

deb-src http://old-releases.ubuntu.com/ubuntu lucid-backports main restricted universe multiverse  

4、更新源

sudo apt-get update