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New Member

Multicast in Cat6500

.My customer uses a C6500 with MSFC and reports follwing behaviour.

He has set a multicast MAC in the cam table with 'set cam permanent'.

It seems that despite the "set cam permanent", a packet with this destination MAC address sent by the MSFC

(after the MSFC has routed it) to the switching engine is replicated to

every ports of the destination VLAN .

This does not happen if a frame with this multicast Dest MAC enters the

switch on any port of the VLAN: in this case, it is only forwarded to the port(s) with the "set cam perm". The flooding of the multicast packet to every ports of the destination VLAN happens only when coming from the MSFC .

Before starting to debug this problem, I would like to know

if somebody can verify this behaviour ? Regards Guenther

New Member

Re: Multicast in Cat6500

This looks like a bug to me.

You could search for known bugs in the Bug Toolkit available in under tools and utilities

New Member

Re: Multicast in Cat6500

It depends(ones more) low (0100.5e00.00xx) multicast MAC addresses are different handled as the normal range (> xx / IP how use IGMP.

It sounds like the solution from stone beat how create a bridge loop if the catalyst does what configuration contains (two antidirected set cam permanent and a static arp unicast ip to a multicast mac).

Regards, Andy