From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Date: Fri, 31 Jul 2015 09:30:07 -0700 From: Stephen Hemminger Message-ID: <20150731093007.290703fe@urahara> In-Reply-To: References: <20150731135728.GG6366@odroid> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable Subject: Re: [Bridge] Multicast packets are not bridged from ethernet to wireless interface List-Id: Linux Ethernet Bridging List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: saurav barik Cc: bridge@lists.linux-foundation.org On Fri, 31 Jul 2015 19:56:12 +0530 saurav barik wrote: > Thanks Linus. > Sorry, it will not be possible to move to recent kernel. >=20 > How does the mdb gets updated for multicast addresses? Is it learnt on > basis of packets received from the network? For example, the multicast > address I use for iperf is 234.100.100.100. I mentioned two scenarios in = my > earlier email. In case of eth0 being the active port on the mbr (multicast > working scenario), I see br_multicast_new_group() and > br_multicast_add_group() being called for this IP address moments after m= br > is up. However in case of wlan0 as the uplink port of mbr, I don't see > those functions being called. >=20 > I guess for unicast packets, if the entry is not present in fdb, the pack= et > is flooded on all other ports and its learnt and added to fdb based on the > port on which response packet arrives. Is it true for Multicast packets t= oo? >=20 > Regards, > Saurav >=20 > On Fri, Jul 31, 2015 at 7:27 PM, Linus L=C3=BCssing > wrote: >=20 > > Hi Saurav, > > > > On Fri, Jul 31, 2015 at 03:50:35PM +0530, saurav barik wrote: > > > I am working on an Access Point device (AP1) running linux kernel 3.0= .34 > > on > > > which my bridge configuration is as follows. > > > > There were quite some crucial bugs, I'm not quite sure whether > > 3.0.34 was actually usuable for multicast snooping. > > > > Any chance to try a recent kernel? > > > > Cheers, Linus > > Multicast forwarding table is built off IGMP messages When application joins a multicast group an IGMP is sent, and bridge snoops for that.