1 备份 sources.list

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

2 编辑 sources.list

rm /etc/apt/sources.list
vim /etc/apt/sources.list

3 选择其中一种国内源粘贴进去

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

#163 guangdong
deb http://mirrors.163.com/ubuntu/ trusty main restricted universe multiverse
deb http://mirrors.163.com/ubuntu/ trusty-security main restricted universe multiverse
deb http://mirrors.163.com/ubuntu/ trusty-updates main restricted universe multiverse
deb http://mirrors.163.com/ubuntu/ trusty-proposed main restricted universe multiverse
deb http://mirrors.163.com/ubuntu/ trusty-backports main restricted universe multiverse
deb-src http://mirrors.163.com/ubuntu/ trusty main restricted universe multiverse
deb-src http://mirrors.163.com/ubuntu/ trusty-security main restricted universe multiverse
deb-src http://mirrors.163.com/ubuntu/ trusty-updates main restricted universe multiverse
deb-src http://mirrors.163.com/ubuntu/ trusty-proposed main restricted universe multiverse
deb-src http://mirrors.163.com/ubuntu/ trusty-backports main restricted universe multiverse

#aliyun
deb-src http://archive.ubuntu.com/ubuntu xenial main restricted
deb http://mirrors.aliyun.com/ubuntu/ xenial main restricted
deb-src http://mirrors.aliyun.com/ubuntu/ xenial main restricted multiverse universe
deb http://mirrors.aliyun.com/ubuntu/ xenial-updates main restricted
deb-src http://mirrors.aliyun.com/ubuntu/ xenial-updates main restricted multiverse universe
deb http://mirrors.aliyun.com/ubuntu/ xenial universe
deb http://mirrors.aliyun.com/ubuntu/ xenial-updates universe
deb http://mirrors.aliyun.com/ubuntu/ xenial multiverse
deb http://mirrors.aliyun.com/ubuntu/ xenial-updates multiverse
deb http://mirrors.aliyun.com/ubuntu/ xenial-backports main restricted universe multiverse
deb-src http://mirrors.aliyun.com/ubuntu/ xenial-backports main restricted universe multiverse
deb http://archive.canonical.com/ubuntu xenial partner
deb-src http://archive.canonical.com/ubuntu xenial partner
deb http://mirrors.aliyun.com/ubuntu/ xenial-security main restricted
deb-src http://mirrors.aliyun.com/ubuntu/ xenial-security main restricted multiverse universe
deb http://mirrors.aliyun.com/ubuntu/ xenial-security universe
deb http://mirrors.aliyun.com/ubuntu/ xenial-security multiverse


#tsinghua.edu
deb http://mirrors.tuna.tsinghua.edu.cn/ubuntu/ xenial main restricted
deb http://mirrors.tuna.tsinghua.edu.cn/ubuntu/ xenial-updates main restricted
deb http://mirrors.tuna.tsinghua.edu.cn/ubuntu/ xenial universe
deb http://mirrors.tuna.tsinghua.edu.cn/ubuntu/ xenial-updates universe
deb http://mirrors.tuna.tsinghua.edu.cn/ubuntu/ xenial multiverse
deb http://mirrors.tuna.tsinghua.edu.cn/ubuntu/ xenial-updates multiverse
deb http://mirrors.tuna.tsinghua.edu.cn/ubuntu/ xenial-backports main restricted universe multiverse
deb http://mirrors.tuna.tsinghua.edu.cn/ubuntu/ xenial-security main restricted
deb http://mirrors.tuna.tsinghua.edu.cn/ubuntu/ xenial-security universe
deb http://mirrors.tuna.tsinghua.edu.cn/ubuntu/ xenial-security multiverse

#neu.edu
deb-src http://mirror.neu.edu.cn/ubuntu/ xenial main restricted #Added by software-properties
deb http://mirror.neu.edu.cn/ubuntu/ xenial main restricted
deb-src http://mirror.neu.edu.cn/ubuntu/ xenial restricted multiverse universe #Added by software-properties
deb http://mirror.neu.edu.cn/ubuntu/ xenial-updates main restricted
deb-src http://mirror.neu.edu.cn/ubuntu/ xenial-updates main restricted multiverse universe
deb http://mirror.neu.edu.cn/ubuntu/ xenial universe
deb http://mirror.neu.edu.cn/ubuntu/ xenial-updates universe
deb http://mirror.neu.edu.cn/ubuntu/ xenial multiverse
deb http://mirror.neu.edu.cn/ubuntu/ xenial-updates multiverse
deb http://mirror.neu.edu.cn/ubuntu/ xenial-backports main restricted universe multiverse
deb-src http://mirror.neu.edu.cn/ubuntu/ xenial-backports main restricted universe multiverse
deb http://archive.canonical.com/ubuntu xenial partner
deb-src http://archive.canonical.com/ubuntu xenial partner
deb http://mirror.neu.edu.cn/ubuntu/ xenial-security main restricted
deb-src http://mirror.neu.edu.cn/ubuntu/ xenial-security main restricted multiverse universe
deb http://mirror.neu.edu.cn/ubuntu/ xenial-security universe
deb http://mirror.neu.edu.cn/ubuntu/ xenial-security multiverse

4 更新源

apt-get update