Google Home Remote Feature

[opninja]

Flat network, 10.0.0.0/24

Versions:
OPNsense 25.1.3-amd64
FreeBSD 14.2-RELEASE-p2
OpenSSL 3.0.16

The only way I've found to make the google home remote feature work for android devices is to toggle a udpbroadcastrelay mdns rule from on to off. Afterwards the google home remote feature immediately works as intended for a temporary period and eventually stops working at some point. To clarify, the remote feature does not work while the rule is enabled, only when toggled back to the off\disabled position does it allow the google home remote feature to immediately start working.

Can someone please assist with resolving this issue. Providing a way to automate the web ui rule toggle would suffice as well. I can create a cron job to schedule the toggle similar to my current workaround for sslh which periodically crashes and needs to be started via a script that checks if its down.

Note: my assumption is that udpbroadcastrelay should not be needed on a flat network but was the only way to get mdns to work and allow the google home feature to work, which is why it is being used in the first place, same experience using both udp relay and mdns repeater, have to toggle on and off in order to allow the google home remote feature to work, nothing is showing as being blocked in the firewall logs, does not appear to be firewall related, seems to be an mdns issue.

Update: found a way to automate the toggle, leave the rule enabled then disable the service, enable\disable the udpbroadcastrelay service periodically via cron job, this resolves the issue and allows the remote feature to work for now
configctl udpbroadcastrelay start
configctl udpbroadcastrelay stop

[EricPerl]

What's your OPN domain? System > Settings > General > Domain.

[opninja]

What's your OPN domain? System > Settings > General > Domain.

localdomain

[EricPerl]

I haven't used mDNS much, but I've read about it.
My understanding is that it the FW should be irrelevant.
This said, OPN being in the .local domain can throw a wrench in the entire subnet. That might extend to other hosts.

I have no clue what start/stop on the plugin might do. It likely depends on its configuration. What is it?
Maybe it repeats on LAN for long enough and the result ends up being cached on devices in the subnet...
Maybe something else is getting in the way of the multicast? Like Guest network behavior on a WLAN.

Wireshark and packet captures looking for UDP traffic on port 5353?

[dseven]

I'm rather confused by your problem description.

You state that udpbroadcastrelay was required to make Google Home work, but also state that Google Home doesn't work if some rule relating to udpbroadcastrelay is enabled. What does this rule do, exactly? Is it a firewall rule, or something else?

Also, you suggest that you have a "flat network" with a single subnet (10.0.0.0/24). If so, what udpbroadcastrelay relaying between? Normally it would be used to relay between multiple LAN interfaces/subnets.

Your hack may seem to make the problem go away for now, but it seems that you haven't really diagnosed and solved the root issue.