备份APT配置文件

cd /etc/apt
sudo cp sources.list sources.list.bak

更换阿里云APT源

cd /etc/apt
#清空原配置文件
sudo > sources.list
#添加阿里云APT源
sudo echo "deb http://mirrors.aliyun.com/debian  stable main contrib non-free" >> sources.list
sudo echo "deb http://mirrors.aliyun.com/debian  stable-updates main contrib non-free" >> sources.list

更新APT

sudo apt update