From logcheck on a server recently upgraded to trixie:

On any Debian system new enough to be supportable, /var/run is always a
deprecated alias for /run (via a symlink, bind-mount or similar
mechanism), so replacing it with /run is always appropriate. Please
update the systemd unit as suggested.

Dear Maintainer,

   * What led up to the situation?

After upgrading to trixie I get this error in saslauthd logs

Feb 27 13:15:29 comms-staging systemd[1]:
/usr/lib/systemd/system/saslauthd.service:8: PIDFile= references a path below
legacy directory /var/run/, updating /var/run/saslauthd/saslauthd.pid →
/run/saslauthd/saslauthd.pid; please update the unit file accordingly.

   * What exactly did you do (or not do) that was effective (or
     ineffective)?

I tried to set the path in /etc/saslauthd and in
/etc/systemd/system/saslauthd.service.d/override.conf to
/var/spool/postfix/run/saslauthd/saslauthd.pid

[Service]
PIDFile=/var/spool/postfix/run/saslauthd/saslauthd.pid

   * What was the outcome of this action?

But ldap authentication failed and I had to switch it back to
/var/spool/postfix/var/run/saslauthd/saslauthd.pid

   * What outcome did you expect instead?

I think /run/saslauthd should work or systemd should not give this warning.

This was the postfix error when switching from /var/run to /run (in
/etc/default, systemd service updated to take pidfile from this file -
https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=1053472#35, directory
permissions updated as required)

2026-03-01T06:38:13.306321-08:00 comms-staging postfix/submission
/smtpd[2102]: warning: SASL authentication failure: cannot connec
t to saslauthd server: No such file or directory

Is the path hard coded in postfix? I did restart both postfix and
saslauthd? How do we tell postfix to look in
/var/spool/postfix/run/saslauthd ?

This works after symlinking var/run to run inside the chroot.

root@comms-staging:/var/spool/postfix/var# ln -s ../run .