进入更新源文件所在目录:
cd /etc/apt/
备份原有更新源文件:
sudo cp -p sources.list sources.list.bak
编辑更新源文件:
sudo gedit sources.list
deb http://mirrors.ustc.edu.cn/ubuntu/ xenial main restricted universe multiverse
deb http://mirrors.ustc.edu.cn/ubuntu/ xenial-security main restricted universe multiverse
deb http://mirrors.ustc.edu.cn/ubuntu/ xenial-updates main restricted universe multiverse
deb http://mirrors.ustc.edu.cn/ubuntu/ xenial-proposed main restricted universe multiverse
deb http://mirrors.ustc.edu.cn/ubuntu/ xenial-backports main restricted universe multiverse
deb-src http://mirrors.ustc.edu.cn/ubuntu/ xenial main restricted universe multiverse
deb-src http://mirrors.ustc.edu.cn/ubuntu/ xenial-security main restricted universe multiverse
deb-src http://mirrors.ustc.edu.cn/ubuntu/ xenial-updates main restricted universe multiverse
deb-src http://mirrors.ustc.edu.cn/ubuntu/ xenial-proposed main restricted universe multiverse
deb-src http://mirrors.ustc.edu.cn/ubuntu/ xenial-backports main restricted universe multiversedeb http://old-releases.ubuntu.com/ubuntu disco main restricted
deb http://old-releases.ubuntu.com/ubuntu disco-updates main restricted
deb http://old-releases.ubuntu.com/ubuntu disco-security main restricted
上面的中科大源可以直接完全替换sources.list内容
更新系统:
sudo apt-get update
sudo apt-get upgrade