1.备份源文件
cp /etc/apt/sources.list /etc/apt/sources.list.bak
2.打开源文件,注释默认的源
vim /etc/apt/sources.list
## 注释原本内容 # deb http://mirrors.ivolces.com/ubuntu/ focal main restricted universe multiverse # deb-src http://mirrors.ivolces.com/ubuntu/ focal main restricted universe multiverse# deb http://mirrors.ivolces.com/ubuntu/ focal-security main restricted universe multiverse # deb-src http://mirrors.ivolces.com/ubuntu/ focal-security main restricted universe multiverse# deb http://mirrors.ivolces.com/ubuntu/ focal-updates main restricted universe multiverse # deb-src http://mirrors.ivolces.com/ubuntu/ focal-updates main restricted universe multiverse# deb http://mirrors.ivolces.com/ubuntu/ focal-proposed main restricted universe multiverse # deb-src http://mirrors.ivolces.com/ubuntu/ focal-proposed main restricted universe multiverse# deb http://mirrors.ivolces.com/ubuntu/ focal-backports main restricted universe multiverse # deb-src http://mirrors.ivolces.com/ubuntu/ focal-backports main restricted universe multiverse## 添加新内容deb http://mirrors.aliyun.com/ubuntu/ focal main restricted universe multiverse deb-src http://mirrors.aliyun.com/ubuntu/ focal main restricted universe multiversedeb http://mirrors.aliyun.com/ubuntu/ focal-security main restricted universe multiverse deb-src http://mirrors.aliyun.com/ubuntu/ focal-security main restricted universe multiversedeb http://mirrors.aliyun.com/ubuntu/ focal-updates main restricted universe multiverse deb-src http://mirrors.aliyun.com/ubuntu/ focal-updates main restricted universe multiversedeb http://mirrors.aliyun.com/ubuntu/ focal-proposed main restricted universe multiverse deb-src http://mirrors.aliyun.com/ubuntu/ focal-proposed main restricted universe multiversedeb http://mirrors.aliyun.com/ubuntu/ focal-backports main restricted universe multiverse deb-src http://mirrors.aliyun.com/ubuntu/ focal-backports main restricted universe multiverse
3.保存退出ESC+:wq!
4.更新源
apt-get update
5.更新系统软件
apt-get dist-upgrade apt-get upgrade