Ubuntu14.04 LTS更新源
一、备份源列表
sudo cp /etc/apt/sources.list /etc/apt/sources.list_backup
二、更新源
sudo vi /etc/apt/sources.list
从下面列表中选择合适的源，替换掉文件中所有的内容，保存编辑好的文件:
注意：一定要选对版本。然后，刷新列表: sudo apt-get update
网易163更新服务器（广东广州电信/联通千兆双线接入），包含其他开源镜像：
deb trusty main restricted universe multiverse
deb trusty-security main restricted universe multiverse
deb trusty-updates main restricted universe multiverse
deb trusty-proposed main restricted universe multiverse
deb trusty-backports main restricted universe multiverse
deb-src trusty main restricted universe multiverse
deb-src trusty-security main restricted universe multiverse
deb-src trusty-updates main restricted universe multiverse
deb-src trusty-proposed main restricted universe multiverse
deb-src trusty-backports main restricted universe multiverse
Ubuntu 16.04 LTS国内快速更新源
一、源文件位置
备份并替换/etc/apt/sources.list的源内容：
二、更改源文件内容
sudo vi /etc/apt/sources.list
deb xenial main restricted universe multiverse
deb xenial-security main restricted universe multiverse
deb xenial-updates main restricted universe multiverse
deb xenial-backports main restricted universe multiverse
##测试版源
deb xenial-proposed main restricted universe multiverse
# 源码
deb-src xenial main restricted universe multiverse
deb-src xenial-security main restricted universe multiverse
deb-src xenial-updates main restricted universe multiverse
deb-src xenial-backports main restricted universe multiverse
##测试版源
deb-src xenial-proposed main restricted universe multiverse
# Canonical 合作伙伴和附加
deb xenial partner
deb xenial main
参考网站：