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Multicasting issues with WAE connected to Router Hwic card

I have multiple sites with WAE's deployed for a DMS implementation. I have a standard multicast configuration that has been tested and applied to all remote sites. The config simply enables multicast routing globally and ip pim sparse mode on the respective networks ie. the WAE network and user data networks.

The remote site topologies are very mixed. I have had success delivering multicast traffic to sites with l3 switch ie. 6500, 3750, 4500 and have also had success using the NME-502 module internal interface.

My issue was discovered at a few odd ball sites that have 2800 series routers w/ 4 port HWIC switch port cards. At these sites the topology would be very simple 2811 -- 2960 - users, and because of the amount of users at the site the WAE appliance was scaled up to a 612. The WAE 612 is connected to the 2811 hwic card and WCCP is fully configured, tested, and is working.

For the multicast to work at all of these sites I must pre-position the streams at each remote site, the WAE then forwards the multicast group information and data out to the routers. But in the case with the 612 connected to the HWIC the multicast traffic for whatever reason is never forwarded out the interface to the rest of the network. I have opened a TAC case but have had no resolve as of yet. Just wondering if anyone in the community has experienced WAE's not forwarding multicast traffic out the HWIC cards.

Obviously the description I have included is very vague. My multicast configuration is correct, I think I am hitting either a software bug or hardware limitation?

comments? suggestions?

ps I have tried dense mode in the same scenario with no luck.


Re: Multicasting issues with WAE connected to Router Hwic card

The most common reasons that routers fail to forward multicast (mcast, multi-cast, PIM) packets are due to Reverse Path Forwarding (RPF) failures and Time-to-Live (TTL) failures.

When troubleshooting multicast routing, the primary concern is the source address. Multicast routing won't forward a packet unless the source of the packet passes a Reverse Path Forwarding (RPF) check. Once a packet passes this RPF check, multicast routing forwards the packet based only upon the destination address. When a multicast packet arrives on an interface, the RPF process checks to ensure that this incoming interface is the outgoing interface used by unicast routing to reach the source of the multicast packet. This RPF check process prevents loops.

IP Multicast Troubleshooting Guide: