我已经使用testing了一段时间，并且想要一个更多的stable系统，所以我认为实现这一目标的最佳方法是将我的系统固定到buster.
我知道降级是有风险的，但我认为这应该是一个侧级，因此没有风险？
这是我当前的设置：
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$ cat /etc/apt/sources.list
# I've added non-free, to allow installation of nvidia-driver
deb http://ftp.us.debian.org/debian/ testing main contrib non-free
deb-src http://ftp.us.debian.org/debian/ testing main
deb http://security.debian.org/debian-security testing-security main
deb-src http://security.debian.org/debian-security testing-security main
deb http://ftp.us.debian.org/debian/ testing-updates main
deb-src http://ftp.us.debian.org/debian/ testing-updates main
deb http://deb.debian.org/debian stretch-backports main contrib non-free
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$ cat /etc/debian_version
buster/sid
我可以：
更改所有
testingtobuster或相关镜像运行
apt update+apt dist-upgrade
所以我的新/etc/apt/sources.list：
deb http://deb.debian.org/debian/ buster main contrib non-free
deb-src http://deb.debian.org/debian/ buster main contrib non-free
deb http://deb.debian.org/debian/ buster-updates main
deb-src http://deb.debian.org/debian/ buster-updates main
deb http://deb.debian.org/debian-security buster/updates main
deb-src http://deb.debian.org/debian-security buster/updates main
deb http://ftp.debian.org/debian buster-backports main contrib non-free
deb-src http://ftp.debian.org/debian buster-backports main contrib non-free