Bug#1101975: systemd-resolved: resolved no longer resolves mdns, despite being configured to

[Herbert Snorrason]

Package: systemd-resolved
Version: 257.4-9
Severity: normal
X-Debbugs-Cc: methanal at gmail.com

After an upgrade today, resolved appears to have stopped resolving mDNS queries,
despite previously having done so and still being configured to do so. This
appears to be the result of a new override file that appeared in the
package. Unlike multiple other changes that require action to maintain an
existing configuration, I did not get any sort of alert in the upgrade process.

I am aware that I can alter my configuration to override the override, but I do
have to wonder if it isn't more appropriate for the package to alter the default
configuration file than to override whatever is in the configuration file. At
the very least, it should be possible to alert users to the need for a
configuration change, rather than assuming that users will know why things have
broken.

-- System Information:
Debian Release: trixie/sid
  APT prefers unstable
  APT policy: (500, 'unstable'), (1, 'experimental')
Architecture: amd64 (x86_64)
Foreign Architectures: i386

Kernel: Linux 6.12.21-amd64 (SMP w/24 CPU threads; PREEMPT)
Kernel taint flags: TAINT_WARN
Locale: LANG=en_GB.UTF-8, LC_CTYPE=en_GB.UTF-8 (charmap=UTF-8), LANGUAGE not set
Shell: /bin/sh linked to /usr/bin/dash
Init: systemd (via /run/systemd/system)
LSM: AppArmor: enabled

Versions of packages systemd-resolved depends on:
ii  dbus [default-dbus-system-bus]  1.16.2-2
ii  libc6                           2.41-6
ii  libssl3t64                      3.4.1-1
ii  libsystemd-shared               257.4-9
ii  systemd                         257.4-9

Versions of packages systemd-resolved recommends:
ii  libidn2-0          2.3.8-2
ii  libnss-myhostname  257.4-9
ii  libnss-resolve     257.4-9

Versions of packages systemd-resolved suggests:
ii  polkitd  126-2

-- Configuration Files:
/etc/systemd/resolved.conf changed:
[Resolve]
MulticastDNS=yes
LLMNR=no


-- no debconf information