Ubuntu 12.04更新软件源

手动修改方式：

163源

deb precise main restricted
deb-src precise main restricted
deb precise-updates main restricted
deb-src precise-updates main restricted
deb precise universe
deb-src precise universe
deb precise-updates universe
deb-src precise-updates universe
deb precise multiverse
deb-src precise multiverse
deb precise-updates multiverse
deb-src precise-updates multiverse
deb precise-backports main restricted universe multiverse
deb-src precise-backports main restricted universe multiverse
deb precise-security main restricted
deb-src precise-security main restricted
deb precise-security universe
deb-src precise-security universe
deb precise-security multiverse
deb-src precise-security multiverse
deb precise main
deb-src precise main

sohu源

deb precise main restricted
deb-src precise main restricted
deb precise-updates main restricted
deb-src precise-updates main restricted
deb precise universe
deb-src precise universe
deb precise-updates universe
deb-src precise-updates universe
deb precise multiverse
deb-src precise multiverse
deb precise-updates multiverse
deb-src precise-updates multiverse
deb precise-backports main restricted universe multiverse deb-src precise-backports main restricted universe multiverse deb precise-security main restricted deb-src precise-security main restricted
deb precise-security universe
deb-src precise-security universe
deb precise-security multiverse
deb-src precise-security multiverse
deb precise main
deb-src precise main

使用方式：

sudo gedit /etc/apt/sources.list

然后把里面的列表替换成上面的列表，保存退出即可，修改完之后最好刷新一下系统的源：

sudo apt-get update 系统修改方式：

事实上，Ubuntu 已经收录了国内大部分知名的源，所以无需上网查找。

打开软件中心 – 编辑 – 软件源 ，然后点击源的列表 – 其他站点：

然后可以自己选择一个源，建议163源，比较稳定

选中后，点击右下角的选择服务器即可！