multicast vs broadcast is there a performance difference what is better?

[n3al10]

I am having issues running R65 Cluster XL UTM 2050 Cluster on multicast.

When I set it to broadcast things work fine. Biggest issue I have seen is alerts that the HA Cluster Sync interface is flapping.

I disabled igmp snooping on the Cisco 2950 switch that the two devices cluster sync interface plugs into but that did not seem to help.

Does igmp snooping need to be turned off on all cisco switches that the firewalls plug into?

Lastly is there a major performance difference of running the cluster in broadcast instead of multicast? Any reason why multicast is better?

It hard to find an answer...

[melipla]

Originally Posted by n3al10

Does igmp snooping need to be turned off on all cisco switches that the firewalls plug into?

While trying to troubleshoot the cause of one of my interfaces going up and down with support, they told me that every cisco device (even ones not directly connected) should have igmp snooping disabled. They had me set it to broadcast (which it already was) in order to avoid any igmp snooping issues. Whether or not that means its true should probably be answered by someone more familiar with Cisco devices than I.

Originally Posted by n3al10

Lastly is there a major performance difference of running the cluster in broadcast instead of multicast? Any reason why multicast is better?

I think the reason is because its multicasting packets. That means less packets have to be sent in order to communicate status to other gateways in the cluster. In large clusters I could see this as being a benefit.