而不是有/etc/apt/preferences文件。我做了以下-
$ cat 99default_release
APT::Default-Release "testing";
以下是/etc/apt/sources.list——
$ cat /etc/apt/sources.list
#### Debian buster #########
deb http://deb.debian.org/debian/ buster main contrib non-free
deb-src http://deb.debian.org/debian buster main contrib non-free
#### Debian unstable #########
deb http://deb.debian.org/debian unstable main contrib non-free
deb-src http://deb.debian.org/debian unstable main contrib non-free
#### Debian experimental #########
deb http://deb.debian.org/debian experimental main contrib
deb-src http://deb.debian.org/debian experimental main contrib
##### Debian Debug packages #######
deb http://debug.mirrors.debian.org/debian-debug/ buster-debug main
deb http://debug.mirrors.debian.org/debian-debug/ unstable-debug main
deb http://debug.mirrors.debian.org/debian-debug/ experimental-debug main
######## Third party repos #######
deb https://riot.im/packages/debian/ stretch main
deb https://lxqt.debian.net/debian experimental-snapshots main
deb-src https://lxqt.debian.net/debian experimental-snapshots main
它似乎确实完成了这项工作 -
$ apt-cache policy
Package files:
100 /var/lib/dpkg/status
release a=now
500 https://lxqt.debian.net/debian experimental-snapshots/main amd64 Packages
release o=lxqt,n=experimental-snapshots,c=main,b=amd64
origin lxqt.debian.net
990 https://riot.im/packages/debian stretch/main amd64 Packages
release o=riot.im,a=testing,n=stretch,c=main,b=amd64
origin riot.im
1 http://debug.mirrors.debian.org/debian-debug experimental-debug/main amd64 Packages
我可能需要考虑的唯一“陷阱”是，当 Buster 发布时，将其重命名为99default_releaseBuster，并且在一两个月内不删除不稳定的存储库。
我还缺少其他东西吗？
我知道冻结和释放还有很长的路要走
https://wiki.debian.org/DebianBuster
可能是完全冻结后 2-3 个月，或者如果我们幸运的话，时间会少于这个时间。