Blocking multicast traffic through OpenWRT switch/Access point, is it possible?

Installing and Using OpenWrt Network and Wireless Configuration
1

So my understanding, is traffic that is bridged through switch, OpenWRT doesnt see at the IP level so firewall rules wouldnt work? I assume I would need to route everything through the CPU and then I could use OpenWRT firewall?

The problem is mainly multicast noise from android devices such as phones, or firetv stick. Cant really disable at the device level due to how they are designed. Even a rooted phone with mdns disabled is generating multicast noise.

Am I even thinking in the right ballpark how this could be done, would like some insight, thank you.

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If the devices are all wireless, you can enable the isolate setting. This only works if all devices are on the same SSID.

But generally, you cannot firewall traffic in the same LAN, as the traffic doesn't traverse the firewall.

Another alternative is to create and place the devices on different networks/LANs.

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Hi, the isolate setting is on, but I see reports in firewall log on other devices, multicast traffic, all link local IPv6, which I tracked to Android devices over the restricted virtual access point with isolation ticked. It doesnt escape the VLAN, but does hit other devices on the VLAN.

Sorry just reread your post, I misunderstood you, its wired devices that seem to be seeing this, so I guess the isolate at least keeping the wireless devices sharing the SSID free of the noise.

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4

Yes, you can block IPv4 multicast packets using bridge firewall (not fw4)

5

Be careful. Blindlessly blocking multicast will i.e. result in non working IPv6.

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