I try to set up a dumb AP with IPV6, however after long time debug, I found all IPV6 multicast packets got lost when send to wlan. There is no problem when ethernet to ethernet.
ping ff02::1 from ethernet -> all ethernet and router (dumb AP) response.
ping ff02::1 from router -> all ethernet and router (dumb AP) response.
ping ff02::1 from wifi -> all ethernet and router (dumb AP) response.
WiFi clients can ping ff02::1 and got response, which how they get IPV6 RA.
But anyone ping ff02::1 will not reached to any WiFi client.
Router: Linksys WRT1900AC v1
OpenWRT 19.07.2, also not works in 18.06
IGMP snooping and STP are disabled.
dnsmasq/odhcpd/firewall are disabled.
OpenWRT built-in RA/DHCPv6/NDP proxy are disabled.
Change net.ipv6.conf.all.mc_forwarding=1 not works.
All networks splitted to host and guest network using VLAN, and each has its own bridge.
So far I cannot determine where the problem is.
Any suggestions are welcome.