为了提高下载和更新速度

要把默认的Xubuntu源改为阿里云源

切换后需要 sudo apt update 更新源

中文

设置-》软件和更新-》

下载自

其他站点

中国

选择aliyun.com

使用指令

cp /etc/apt/source.list /etc/apt/source.list.backup

vi /etc/apt/source.list

vi使用，按d是删除行，按i是插入。先d删除全部内容然后按i复制一下内容，然后按: 输入qw!

deb cdrom:[Ubuntu 16.04 LTS Xenial Xerus - Release amd64 (20160420.1)]/ xenial main restricted

deb-src http://archive.ubuntu.com/ubuntu xenial main restricted #Added by software-properties

deb-src http://mirrors.aliyun.com/ubuntu/ xenial main restricted multiverse universe #Added by software-properties

deb http://mirrors.aliyun.com/ubuntu/ xenial-updates main restricted

deb-src http://mirrors.aliyun.com/ubuntu/ xenial-updates main restricted multiverse universe #Added by software-properties

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 #Added by software-properties

deb http://mirrors.aliyun.com/ubuntu/ xenial-security main restricted

deb-src http://mirrors.aliyun.com/ubuntu/ xenial-security main restricted multiverse universe #Added by software-properties

ubuntu 改为阿里云源