1、备份
sudo cp /etc/apt/sources.list /etc/apt/sources.list.bak
2、编辑
sudo gedit /etc/apt/sources.list
3、覆盖源文件的所有内容
ubantu16.04：
deb http://mirrors.aliyun.com/ubuntu/ xenial main
deb-src http://mirrors.aliyun.com/ubuntu/ xenial main
deb http://mirrors.aliyun.com/ubuntu/ xenial-updates main
deb-src http://mirrors.aliyun.com/ubuntu/ xenial-updates main
deb http://mirrors.aliyun.com/ubuntu/ xenial universe
deb-src http://mirrors.aliyun.com/ubuntu/ xenial universe
deb http://mirrors.aliyun.com/ubuntu/ xenial-updates universe
deb-src http://mirrors.aliyun.com/ubuntu/ xenial-updates universe
deb http://mirrors.aliyun.com/ubuntu/ xenial-security main
deb-src http://mirrors.aliyun.com/ubuntu/ xenial-security main
deb http://mirrors.aliyun.com/ubuntu/ xenial-security universe
deb-src http://mirrors.aliyun.com/ubuntu/ xenial-security universe
ubantu18.04:
deb http://mirrors.aliyun.com/ubuntu/ bionic main restricted universe multiverse
deb-src http://mirrors.aliyun.com/ubuntu/ bionic main restricted universe multiverse
deb http://mirrors.aliyun.com/ubuntu/ bionic-security main restricted universe multiverse
deb-src http://mirrors.aliyun.com/ubuntu/ bionic-security main restricted universe multiverse
deb http://mirrors.aliyun.com/ubuntu/ bionic-updates main restricted universe multiverse
deb-src http://mirrors.aliyun.com/ubuntu/ bionic-updates main restricted universe multiverse
deb http://mirrors.aliyun.com/ubuntu/ bionic-proposed main restricted universe multiverse
deb-src http://mirrors.aliyun.com/ubuntu/ bionic-proposed main restricted universe multiverse
deb http://mirrors.aliyun.com/ubuntu/ bionic-backports main restricted universe multiverse
deb-src http://mirrors.aliyun.com/ubuntu/ bionic-backports main restricted universe multiverse
4、更新
#升级软件列表 sudo apt-get update #系统将现有的Package升级,如果有相依性的问题，而此相依性需要安装其它新的Package或影响到其它Package的相依性时，此Package就不会被升级，会保留下来。 #还有种说法时更新软件，但是会更新系统内核，大版本不变，不完全可靠的消息，没经过测试 sudo apt-get upgrade #可以聪明的解决相依性的问题，如果有相依性问题，需要安装/移除新的Package，就会试着去安装/移除它。会识别出当依赖关系改变的情形并作出处理，而upgrade对此情形不处理。 sudo apt-get dist-upgrade
163源：
可以尝试以下163的源，可能会意想不到的的快。
deb http://mirrors.163.com/ubuntu/ wily main restricted universe multiverse deb http://mirrors.163.com/ubuntu/ wily-security main restricted universe multiverse deb http://mirrors.163.com/ubuntu/ wily-updates main restricted universe multiverse deb http://mirrors.163.com/ubuntu/ wily-proposed main restricted universe multiverse deb http://mirrors.163.com/ubuntu/ wily-backports main restricted universe multiverse deb-src http://mirrors.163.com/ubuntu/ wily main restricted universe multiverse deb-src http://mirrors.163.com/ubuntu/ wily-security main restricted universe multiverse deb-src http://mirrors.163.com/ubuntu/ wily-updates main restricted universe multiverse deb-src http://mirrors.163.com/ubuntu/ wily-proposed main restricted universe multiverse deb-src http://mirrors.163.com/ubuntu/ wily-backports main restricted universe multiverse
参考：
http://mirrors.aliyun.com/（更多源参考阿里云官方提供的源列表）
http://mirrors.163.com/（更多源参考163官方提供的源列表）
http://blog.csdn.net/paincupid/article/details/52895676
http://www.2cto.com/os/201301/183519.html
http://www.baiyuxiong.com/?p=529、