Open-Mesh » batman-adv

First, Thanks for your support and thanks in advance.

There is a mention that a routable multicast address(239.1.2.3)is supported by multicast optimization with bridges,
if it is 5.14 kernel or newer and batman-adv 2021.2 or newer.(https://www.open-mesh.org/projects/batman-adv/wiki/Multicast-optimizations-tech)

However, I can see the log message that
"[ 87.971093] batman_adv: bat0: No IGMP Querier present - multicast optimizations disabled
[ 87.971108] batman_adv: bat0: No MLD Querier present - multicast optimizations disabled"
And I tested as below and it looks like multicast optimization does not work with bridges.

Can I know multicast optimization can be supported with bridges if we meet any kind of condition if there are?

Test environment
1. Raspberry pi4 with bookworm.
2. Linux kernel : 6.12.20
3. batman-adv : 2024.02

Test Process
1. Connect 3 raspberry pi with batman mesh. 2 of them are bridged to connect other computers to the mesh network.
2. One computer send multicast message(239.1.2.3) and other 2 devices listen to the multicast.
3. Set multicast_fanout to 1 in order to make multicast forwarding instead of unicast.
4. Observe wi-fi interface to check the type of multicast transmission(whether it is broadcast/uni-cast/multicast)

Expected:
1. Multicast type because it uses routable multicast.

Actual result
If it is under fanout number, there is unicast.
If it is more than fanout number, there is broadcast.

Thanks.