Dnsmasq stops occasionaly

[ligand]

disable RA advertisement
  PID  RSS COMMAND
97469 7124 /usr/local/sbin/dnsmasq -x /var/run/dnsmasq.pid -C /usr/local/etc/dnsmasq.conf
Sat Jan 17 18:03:01 EST 2026
  PID  RSS COMMAND
97469 9884 /usr/local/sbin/dnsmasq -x /var/run/dnsmasq.pid -C /usr/local/etc/dnsmasq.conf
Sat Jan 17 19:03:01 EST 2026
  PID   RSS COMMAND
97469 14064 /usr/local/sbin/dnsmasq -x /var/run/dnsmasq.pid -C /usr/local/etc/dnsmasq.conf
Sat Jan 17 20:03:01 EST 2026
  PID   RSS COMMAND
97469 16096 /usr/local/sbin/dnsmasq -x /var/run/dnsmasq.pid -C /usr/local/etc/dnsmasq.conf
Sat Jan 17 21:03:02 EST 2026
  PID   RSS COMMAND
97469 17256 /usr/local/sbin/dnsmasq -x /var/run/dnsmasq.pid -C /usr/local/etc/dnsmasq.conf
Sat Jan 17 22:03:02 EST 2026
  PID   RSS COMMAND
97469 21000 /usr/local/sbin/dnsmasq -x /var/run/dnsmasq.pid -C /usr/local/etc/dnsmasq.conf
Sat Jan 17 23:03:02 EST 2026
  PID   RSS COMMAND
97469 22664 /usr/local/sbin/dnsmasq -x /var/run/dnsmasq.pid -C /usr/local/etc/dnsmasq.conf
Sun Jan 18 00:03:02 EST 2026
  PID   RSS COMMAND
97469 24208 /usr/local/sbin/dnsmasq -x /var/run/dnsmasq.pid -C /usr/local/etc/dnsmasq.conf
Sun Jan 18 01:03:02 EST 2026
  PID   RSS COMMAND
97469 27100 /usr/local/sbin/dnsmasq -x /var/run/dnsmasq.pid -C /usr/local/etc/dnsmasq.conf
Sun Jan 18 02:03:02 EST 2026
  PID   RSS COMMAND
97469 29020 /usr/local/sbin/dnsmasq -x /var/run/dnsmasq.pid -C /usr/local/etc/dnsmasq.conf
Sun Jan 18 03:03:02 EST 2026
  PID   RSS COMMAND
97469 30472 /usr/local/sbin/dnsmasq -x /var/run/dnsmasq.pid -C /usr/local/etc/dnsmasq.conf
Sun Jan 18 04:03:02 EST 2026
  PID   RSS COMMAND
97469 31488 /usr/local/sbin/dnsmasq -x /var/run/dnsmasq.pid -C /usr/local/etc/dnsmasq.conf
Sun Jan 18 05:03:02 EST 2026
  PID   RSS COMMAND
97469 32776 /usr/local/sbin/dnsmasq -x /var/run/dnsmasq.pid -C /usr/local/etc/dnsmasq.conf
Sun Jan 18 06:03:02 EST 2026
  PID   RSS COMMAND
97469 34176 /usr/local/sbin/dnsmasq -x /var/run/dnsmasq.pid -C /usr/local/etc/dnsmasq.conf
Sun Jan 18 07:03:02 EST 2026
  PID   RSS COMMAND
97469 34896 /usr/local/sbin/dnsmasq -x /var/run/dnsmasq.pid -C /usr/local/etc/dnsmasq.conf
Sun Jan 18 08:03:02 EST 2026

[ligand]

It looks dnsmasq's memory consumption is greatly reduced by turning off RA advertisement... I'm going to turn on the radvd and leave RA off to see if dnsmasq's memory consumption stabilizes.  So to recap my dnsmasq configuration will only serve dhcpv4/v6.  DNS is handled by unbound and RA will be handled by radvd.

[Monviech (Cedrik)]

Thanks for testing, if this is indeed the result and others can verify this as well, we could ask in the dnsmasq mailing list.

[ligand]

Here's something interesting... it looks like there is a problem with serving DHCPv6... so after turning on radvd memory consumption started increasing substantially...

97469 34896 /usr/local/sbin/dnsmasq -x /var/run/dnsmasq.pid -C /usr/local/etc/dnsmasq.conf
Sun Jan 18 08:03:02 EST 2026
  PID   RSS COMMAND
97469 49720 /usr/local/sbin/dnsmasq -x /var/run/dnsmasq.pid -C /usr/local/etc/dnsmasq.conf
Sun Jan 18 09:03:02 EST 2026
  PID   RSS COMMAND
97469 65652 /usr/local/sbin/dnsmasq -x /var/run/dnsmasq.pid -C /usr/local/etc/dnsmasq.conf
Sun Jan 18 10:03:02 EST 2026
  PID   RSS COMMAND
97469 92148 /usr/local/sbin/dnsmasq -x /var/run/dnsmasq.pid -C /usr/local/etc/dnsmasq.conf
Sun Jan 18 11:03:02 EST 2026
  PID    RSS COMMAND
97469 121672 /usr/local/sbin/dnsmasq -x /var/run/dnsmasq.pid -C /usr/local/etc/dnsmasq.conf
Sun Jan 18 12:03:02 EST 2026
  PID    RSS COMMAND
97469 139552 /usr/local/sbin/dnsmasq -x /var/run/dnsmasq.pid -C /usr/local/etc/dnsmasq.conf
Sun Jan 18 13:03:02 EST 2026
  PID    RSS COMMAND
97469 154424 /usr/local/sbin/dnsmasq -x /var/run/dnsmasq.pid -C /usr/local/etc/dnsmasq.conf
Sun Jan 18 14:03:02 EST 2026

[Monviech (Cedrik)]

Could you post your findings to the dnsmasq mailing list to see if you get a response from the author? It would be great if you could do it, since you are affected directly by the issue.

https://lists.thekelleys.org.uk/mailman/listinfo/dnsmasq-discuss

[ligand]

Message sent to the list.  Will keep everyone posted.

[Monviech (Cedrik)]

Thank you, if you need any help or do not know how to get specific information that is requested, let me know.

Backreference: https://www.mail-archive.com/dnsmasq-discuss@lists.thekelleys.org.uk/msg18211.html

[ligand]

HI!  Simon from dnsmasq is asking me to adjust the dnsmasq config as follows:

add
log-queries=extra
log-dhcp
log-facility=/path/to/file

and remove the quiet-* options that are there now.

How do I do this?  The template seems to have a lot of logic in it and I don't want to break anything.

[Monviech (Cedrik)]

Hello,

the quiet options are a small bug in the template, please execute the following in the shell:

opnsense-patch https://github.com/opnsense/core/commit/664c80e7cab26725872c5b6f3ce2a2b6c0f566e5


Afterwards in the Dnsmasq general settings in the GUI select the following (enable advanced mode toggle):

- Log the results of DNS queries
- Log DHCP options and tags

I dont think you need a log facility, dnsmasqs log output is redirected to syslog-ng. You can find all logs in

- /var/log/dnsmasq/...

You can find events like interface up/down events with this command:

- dmesg

Other interesting logs are redirected here:

- /var/log/system/...
- /var/log/configd/...

I would suggest you only run dnsmasq features and not use radvd since that will tighten the scope.

If you need something else let me know.