ubuntu 更换源

1.备份原有的源文件  

cd /etc/apt/

sudo cp -p sources.list sources.list.bak

2.修改源文件

sudo vim sources.list

删除sources.list 文件中所有内容添加一下内容 保存退出。

/******************      18.04源    *****************************************/

deb http://mirrors.aliyun.com/ubuntu/ bionic main restricted universe multiverse

deb-src http://mirrors.aliyun.com/ubuntu/ bionic main restricted universe multiverse

deb http://mirrors.aliyun.com/ubuntu/ bionic-security main restricted universe multiverse

deb-src http://mirrors.aliyun.com/ubuntu/ bionic-security main restricted universe multiverse

deb http://mirrors.aliyun.com/ubuntu/ bionic-updates main restricted universe multiverse

deb-src http://mirrors.aliyun.com/ubuntu/ bionic-updates main restricted universe multiverse

deb http://mirrors.aliyun.com/ubuntu/ bionic-backports main restricted universe multiverse

deb-src http://mirrors.aliyun.com/ubuntu/ bionic-backports main restricted universe multiverse

deb http://mirrors.aliyun.com/ubuntu/ bionic-proposed main restricted universe multiverse

deb-src http://mirrors.aliyun.com/ubuntu/ bionic-proposed main restricted universe multiverse

 /******************      20.04源    *****************************************/

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

3.

sudo  apt-get update 

apt upgrade