Linux拥有众多的发行版，每个发行版都有提供镜像，但是，有些镜像的下载速度参差不齐，偶尔会有更新失败的情况。

下面以修改 Ubuntu 软件源为 清华大学为例进行说明。

镜像地址：http://www.landui.com

香港节点镜像地址：http://www.landui.com

1、备份原配置文件

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

2、更改配置文件

编辑/etc/apt/sources.list文件, 将内容修改为：

Xenial(16.04)

deb http://www.landui.com/ubuntu/ Xenial main restricted universe multiverse

deb http://www.landui.com/ubuntu/ Xenial-security main restricted universe multiverse

deb http://www.landui.com/ubuntu/ Xenial-updates main restricted universe multiverse

deb http://www.landui.com/ubuntu/ Xenial-proposed main restricted universe multiverse

deb http://www.landui.com/ubuntu/ Xenial-backports main restricted universe multiverse

deb-src http://www.landui.com/ubuntu/ Xenial main restricted universe multiverse

deb-src http://www.landui.com/ubuntu/ Xenial-security main restricted universe multiverse

deb-src http://www.landui.com/ubuntu/ Xenial-updates main restricted universe multiverse

deb-src http://www.landui.com/ubuntu/ Xenial-proposed main restricted universe multiverse

deb-src http://www.landui.com/ubuntu/ Xenial-backports main restricted universe multiverse

Trusty(14.04)

deb http://www.landui.com/ubuntu/ Trusty main restricted universe multiverse

deb http://www.landui.com/ubuntu/ Trusty-security main restricted universe multiverse

deb http://www.landui.com/ubuntu/ Trusty-updates main restricted universe multiverse

deb http://www.landui.com/ubuntu/ Trusty-proposed main restricted universe multiverse

deb http://www.landui.com/ubuntu/ Trusty-backports main restricted universe multiverse

deb-src http://www.landui.com/ubuntu/ Trusty main restricted universe multiverse

deb-src http://www.landui.com/ubuntu/ Trusty-security main restricted universe multiverse

deb-src http://www.landui.com/ubuntu/ Trusty-updates main restricted universe multiverse

deb-src http://www.landui.com/ubuntu/ Trusty-proposed main restricted universe multiverse

deb-src http://www.landui.com/ubuntu/ Trusty-backports main restricted universe multiverse

Precise(12.04)

deb http://www.landui.com/ubuntu/ precise main restricted universe multiverse

deb http://www.landui.com/ubuntu/ precise-security main restricted universe multiverse

deb http://www.landui.com/ubuntu/ precise-updates main restricted universe multiverse

deb http://www.landui.com/ubuntu/ precise-proposed main restricted universe multiverse

deb http://www.landui.com/ubuntu/ precise-backports main restricted universe multiverse

deb-src http://www.landui.com/ubuntu/ precise main restricted universe multiverse

deb-src http://www.landui.com/ubuntu/ precise-security main restricted universe multiverse

deb-src http://www.landui.com/ubuntu/ precise-updates main restricted universe multiverse

deb-src http://www.landui.com/ubuntu/ precise-proposed main restricted universe multiverse

deb-src http://www.landui.com/ubuntu/ precise-backports main restricted universe multiverse

如果是香港节点：

编辑/etc/apt/sources.list文件, 将内容修改为：

Xenial(16.04)

deb http://www.landui.com/ubuntu/ Xenial main restricted universe multiverse

deb http://www.landui.com/ubuntu/ Xenial-security main restricted universe multiverse

deb http://www.landui.com/ubuntu/ Xenial-updates main restricted universe multiverse

deb http://www.landui.com/ubuntu/ Xenial-proposed main restricted universe multiverse

deb http://www.landui.com/ubuntu/ Xenial-backports main restricted universe multiverse

deb-src http://www.landui.com/ubuntu/ Xenial main restricted universe multiverse

deb-src http://www.landui.com/ubuntu/ Xenial-security main restricted universe multiverse

deb-src http://www.landui.com/ubuntu/ Xenial-updates main restricted universe multiverse

deb-src http://www.landui.com/ubuntu/ Xenial-proposed main restricted universe multiverse

deb-src http://www.landui.com/ubuntu/ Xenial-backports main restricted universe multiverse

Trusty(14.04)

deb http://www.landui.com/ubuntu/ Trusty main restricted universe multiverse

deb http://www.landui.com/ubuntu/ Trusty-security main restricted universe multiverse

deb http://www.landui.com/ubuntu/ Trusty-updates main restricted universe multiverse

deb http://www.landui.com/ubuntu/ Trusty-proposed main restricted universe multiverse

deb http://www.landui.com/ubuntu/ Trusty-backports main restricted universe multiverse

deb-src http://www.landui.com/ubuntu/ Trusty main restricted universe multiverse

deb-src http://www.landui.com/ubuntu/ Trusty-security main restricted universe multiverse

deb-src http://www.landui.com/ubuntu/ Trusty-updates main restricted universe multiverse

deb-src http://www.landui.com/ubuntu/ Trusty-proposed main restricted universe multiverse

deb-src http://www.landui.com/ubuntu/ Trusty-backports main restricted universe multiverse

Precise(12.04)

deb http://www.landui.com/ubuntu/ precise main restricted universe multiverse

deb http://www.landui.com/ubuntu/ precise-security main restricted universe multiverse

deb http://www.landui.com/ubuntu/ precise-updates main restricted universe multiverse

deb http://www.landui.com/ubuntu/ precise-proposed main restricted universe multiverse

deb http://www.landui.com/ubuntu/ precise-backports main restricted universe multiverse

deb-src http://www.landui.com/ubuntu/ precise main restricted universe multiverse

deb-src http://www.landui.com/ubuntu/ precise-security main restricted universe multiverse

deb-src http://www.landui.com/ubuntu/ precise-updates main restricted universe multiverse

deb-src http://www.landui.com/ubuntu/ precise-proposed main restricted universe multiverse

deb-src http://www.landui.com/ubuntu/ precise-backports main restricted universe multiverse

3、更新

# apt-get update