ubuntu切阿里源

第一步：备份原来的源文件

cd /etc/apt/  

然后会显示下面的源文件sources.list 
输入命令 sudo cp sources.list sources.list.bak 
就是将sources.list备份到sources.list.bak

第二步：替换源

阿里云源的文件

deb http://mirrors.aliyun.com/ubuntu/ xenial main restricted universe multiverse  
deb http://mirrors.aliyun.com/ubuntu/ xenial-security main restricted universe multiverse  
deb http://mirrors.aliyun.com/ubuntu/ xenial-updates main restricted universe multiverse  
deb http://mirrors.aliyun.com/ubuntu/ xenial-backports main restricted universe multiverse  
##测试版源  
deb http://mirrors.aliyun.com/ubuntu/ xenial-proposed main restricted universe multiverse  
# 源码  
deb-src http://mirrors.aliyun.com/ubuntu/ xenial main restricted universe multiverse  
deb-src http://mirrors.aliyun.com/ubuntu/ xenial-security main restricted universe multiverse  
deb-src http://mirrors.aliyun.com/ubuntu/ xenial-updates main restricted universe multiverse  
deb-src http://mirrors.aliyun.com/ubuntu/ xenial-backports main restricted universe multiverse  
##测试版源  
deb-src http://mirrors.aliyun.com/ubuntu/ xenial-proposed main restricted universe multiverse  

替换并保存 sudo gedit sources.list打开文件，替换成阿里云文件即可

第三步：更新源和软件

sudo apt-get update 更新源  
sudo apt-get upgrade 更新软件