Ubuntu 更换阿里云软件源

Ubuntu安装软件有很多问题是因为源的问题，比如Ubuntu14.04安装openjdk-7-jdk可能会出现依赖问题，我曾查找了很多办法都没解决，但是换了阿里云的软件源后问题就解决了。 

阿里云的源很快，下面总结一下如何更换Ubuntu的软件源。

一、备份

sudo cp /etc/apt/sources.list /etc/apt/sources.list.bak 

二、修改

sudo gedit /etc/apt/sources.list

在source.list文件添加一下内容

deb http://mirrors.aliyun.com/ubuntu/ trusty main restricted universe multiverse
deb http://mirrors.aliyun.com/ubuntu/ trusty-security main restricted universe multiverse
deb http://mirrors.aliyun.com/ubuntu/ trusty-updates main restricted universe multiverse
deb http://mirrors.aliyun.com/ubuntu/ trusty-proposed main restricted universe multiverse
deb http://mirrors.aliyun.com/ubuntu/ trusty-backports main restricted universe multiverse
deb-src http://mirrors.aliyun.com/ubuntu/ trusty main restricted universe multiverse
deb-src http://mirrors.aliyun.com/ubuntu/ trusty-security main restricted universe multiverse
deb-src http://mirrors.aliyun.com/ubuntu/ trusty-updates main restricted universe multiverse
deb-src http://mirrors.aliyun.com/ubuntu/ trusty-proposed main restricted universe multiverse
deb-src http://mirrors.aliyun.com/ubuntu/ trusty-backports main restricted universe multiverse

三、更新

sudo apt-get update