Hi,
I have a pair of 6509 switches running IOS 12.2(33)SXI4a. These switches are connected through a port-channel. A vlan is configured on both switches (vlan id 6). Servers are dual homed on these switches.
I have not enabled multicast routing on the devices, but configured PIM Sparse mode on vlan 6 SVI. IGMP snooping is configured. PIM configuration on the interfaces helps achieve IGMP querier redundancy.
I have a multicast sender and receiver connected in vlan 6. The sender is generating 650 Mbps of multicast traffic. I observed that the routing CPU spikes to 45 % during the test. I am trying to find the reason for spike in routing CPU.
Netdr captures taken during the test shows that traffic is being punted to the CPU. I am not able to understand this behaviour as well, as the traffic should be switched at layer 2 in the same vlan.
Hope to get some help in finding the cause of CPU spike.
Rgds,
Aniket