Dear Maintainer,

I'm unsure if this is upstream problem or not, however after updating to
Debian 13 (trixie) I've faced some problems with my configuration and
the culprit was the removal of the /etc/sysctl.conf (and options that
I've set there some time ago).

While I understand and welcome the move to /etc/sysctl.d/*.conf files I
must say that a warning would be nice, either during package
installation or in "Issues to be aware" in the release notes as the
file seems to be silently removed without any message.
If the warning is there then it should be made more visible because I've
made two upgrades but seen zero warnings about this change. Probably
even better solution would be moving the file into /etc/sysctl.d (with
notification) at the lowest priority, however I can see how this will be
rejected.

Thank you in advance and sorry if I filed it wrong (maybe it should've
gone to some release note suggestions?)

In my case, on trixie upgrade, my /etc/sysctl.conf was renamed to
/etc/sysctl.conf.dpkg-bak and therefore disabled.  This caused some
significant breakage, some of which wasn't apparent until a couple of
days later.

In fact, this rename (a consequence of the removal of the actual
conffile) was safe because systemd was no longer reading this file
via a symbolic link. Obviously once this symbolic link has been
removed, procps could not know that this file was actually used
(via such a symbolic link).

It was actually systemd that introduced the breakage while
/etc/sysctl.conf was still existing on current systems, by
removing this symbolic link:

https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=1077184

Ah, that's why I (as the procps maintainer) couldn't see the issue.
i was just removing what I thought was a default config file.

 - Craig