Thanks for the explanation. On Tue, Aug 5, 2025 at 7:37 PM Justin B Rye <[email protected]> wrote: > My understanding was that the reason /etc/sysctl.conf was a symlink is > that systemd doesn't read that file, so it has been deprecated for a > while; [...]
I didn't know about the deprecation. The sysctl.conf manpage says that "procps sysctl" is distinct from systemd-sysctl. It does *not* note the deprecation, but notes that: > Finally, procps sysctl reads /etc/sysctl.conf. This file is not used by > systemd-sysctl, which means that some kernel parameters are not > set depending on the implementation of sysctl that is installed. The first sentence appears to be misleading (/etc/sysctl.conf is no longer listed as a conffile, and is removed by dpkg on upgrade); see: - https://salsa.debian.org/debian/procps/-/commit/77f54cb9d9951b193d2aaeb694e56061309eb3ef - https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=1076352 - https://salsa.debian.org/debian/procps/-/commit/ac03e56e0eab2b4b0d2afa18250c1cf77b14c8de - https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=1085130 - https://salsa.debian.org/debian/procps/-/commit/2f894fe720c2dda8cfc68c0f2873756235f63e9e However, the manpage has actually recently been updated: - https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=1077187 - https://gitlab.com/procps-ng/procps/-/commit/ec590d5145668ea1868e1787c272d329ce5feba1 The bookworm manpage about procps sysctl.conf (https://manpages.debian.org/bookworm/procps/sysctl.conf.5.en.html) also doesn't mention the deprecation (or that /etc/sysctl.conf is specific to procps) at all. Only a systemd changelog entry from 2014 says that: > Create[d] a compat symlink /etc/sysctl.d/99-sysctl.conf as systemd-sysctl no > longer reads /etc/sysctl.conf. To sum up, bookworm changelogs and manpages do not mention the deprecation, and 2014 changelogs only mention that under systemd-sysctl, /etc/sysctl.conf works because of a "compat symlink". Even under trixie, the sysctl.conf manpage is misleading. One has to read the changelogs to learn that /etc/sysctl.conf was *already* automatically removed and is no longer a valid conffile. Therefore, I think that: - the manpage sysctl.conf(5) from procps should mention that /etc/sysctl.conf shouldn't be used anymore; - the release notes should prominently mention that /etc/sysctl.conf shouldn't be used anymore, and that it will be automatically removed on upgrade. Regards, Samuel Plavec
