ubuntu20.04 LTS更换aliyun源

1、sudo vim /etc/apt/source.list

清除该文件内所有内容

 2、替换为以下源

deb http://mirrors.aliyun.com/ubuntu/ focal main restricted
deb http://mirrors.aliyun.com/ubuntu/ focal-updates main restricted
deb http://mirrors.aliyun.com/ubuntu/ focal universe
deb http://mirrors.aliyun.com/ubuntu/ focal-updates universe
deb http://mirrors.aliyun.com/ubuntu/ focal multiverse
deb http://mirrors.aliyun.com/ubuntu/ focal-updates multiverse
deb http://mirrors.aliyun.com/ubuntu/ focal-backports main restricted universe multiverse
deb http://mirrors.aliyun.com/ubuntu/ focal-security main restricted
deb http://mirrors.aliyun.com/ubuntu/ focal-security universe
deb http://mirrors.aliyun.com/ubuntu/ focal-security multiverse

 3、保存，并更新

sudo  apt update
sudo  apt upgrade
//注：root用户下不必加sudo

清华镜像地址：https://mirrors.tuna.tsinghua.edu.cn/help/ubuntu/