由于Debian 10（buster）还比较新，有很多源都使用不了，有的还连接不上，以下是亲自试过可以使用的源，需要的小伙伴可以试试。
163源
# deb cdrom:[Debian GNU/Linux 10.2.0 _Buster_ - Official i386 NETINST 20191116-11:32]/ buster main
#deb cdrom:[Debian GNU/Linux 10.2.0 _Buster_ - Official i386 NETINST 20191116-11:32]/ buster main
deb http://mirrors.163.com/debian/ buster main
deb-src http://mirrors.163.com/debian/ buster main
deb http://security.debian.org/debian-security buster/updates main
deb-src http://security.debian.org/debian-security buster/updates main
# buster-updates, previously known as 'volatile'
deb http://mirrors.163.com/debian/ buster-updates main
deb-src http://mirrors.163.com/debian/ buster-updates main
# This system was installed using small removable media
# (e.g. netinst, live or single CD). The matching "deb cdrom"
# entries were disabled at the end of the installation process.
# For information about how to configure apt package sources,
# see the sources.list(5) manual.
阿里源
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
步骤：
- 备份/etc/apt/sources.list，备份命令
cp /etc/apt/sources.list /etc/apt/sources.list.bak
2.在/etc/apt/sources.list文件中，删除原文件所有内容，添加上面的条目。
注：/etc/apt/sources.list 是包管理工具 apt 所用的记录软件包仓库位置的配置文件
其中，deb：档案类型为二进制预编译软件包，一般我们所用的档案类型。
deb-src：档案类型为用于编译二进制软件包的源代码
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