I bet there's a switch in the mix somewhere and the switch is doing IGMP snooping. The switch doesn't see an IGMP join (because routers don't bother to join for "well-known" groups like "all routers.") So the switch doesn't forward these well-known multicasts. This in an infamous problem. Microsoft has some papers on it. You could search there.
Also, this came up before on this list. Does anyone remember the exact details or have a URL? Priscilla Mohannad Khuffash wrote: > > Hi ... > > I have tried to configure HSRP on two 3660 routers, I > configured them > straight forward where only a little commands needed.But HSRP > don't worked > well ! The reason simply was that they are not seeing the HSRP > hello > messages so every one act as the active one ! When I checked > the problem > more, I discovered that both of them are not seeing the > 224.0.0.2 messages > by using the SHOW IP INTERFACE command where none of the > interfaces of the > two routers are joined for this multicast group ! > My question now is how I can make them joined to 224.0.0.2 > which should be > the default configuration ? Or may be I'm wrong in my > investigation ?! > > Thanks for your help > > -- > > > > > > > > Mohannad Khuffash > > Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=59649&t=59609 -------------------------------------------------- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
