Debian 10(buster)可用的国内软件源如下(阿里云源):
deb http://mirrors.aliyun.com/debian/ buster main non-free contrib deb-src http://mirrors.aliyun.com/debian/ buster main non-free contrib deb http://mirrors.aliyun.com/debian-security buster/updates main deb-src http://mirrors.aliyun.com/debian-security buster/updates main deb http://mirrors.aliyun.com/debian/ buster-updates main non-free contrib deb-src http://mirrors.aliyun.com/debian/ buster-updates main non-free contrib deb http://mirrors.aliyun.com/debian/ buster-backports main non-free contrib deb-src http://mirrors.aliyun.com/debian/ buster-backports main non-free contrib
备份/etc/apt/sources.list
#备份
mv /etc/apt/sources.list /etc/apt/sources.list.bak
vim /etc/apt/sources.list文件
#更新
apt-get update