#1148861 mdns-reflector: Default LOGGING_LEVEL can cause log file space exhaustion

Package:
mdns-reflector
Source:
mdns-reflector
Description:
lightweight and performant multicast DNS (mDNS) reflector
Submitter:
Tj
Date:
2026-09-24 10:37:02 UTC
Severity:
normal
Tags:
#1148861#5
Date:
2026-09-24 10:34:39 UTC
From:
To:
On a space-constrained embedded device used as a gateway (PC Engines
APU2 with 60GiB SSD) I recently noticed that several services journal
logs only had last few days entries in them; usually the logs would
cover several recent boot sessions over several months.

Due to the space constraints the host is configured thus:

dev/mapper/VG_SSD-var  7.8G  5.8G  1.6G  79% /var

# journald.conf
SystemMaxUse=2500M
SystemKeepFree=1G

I found the journal using the maximum:

2.5G    /var/log/journal/2b91f3a904674a7698f80c698fd76904

Eventually I tracked it down using

journalctl --follow

that shows mdns-reflector writing at least 12 messages per second.

Reviewing the default configuration I found:

LOGGING_LEVEL=info

I've now changed it to

LOGGING_LEVEL=warning

and I'd recommend that the Debian package adopts this change too.

I'm reporting it to upstream but since that repository does not appear
to have been changed in 3 years it may not get acted on upstream.