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High collision, cluster pool.

New Member

High collision, cluster pool.


I'm running a setup with two BGP routers, they are using CARP ip load-balancing. This means that the carp interface is using the same MAC address on each server.

When both servers are enabled within the same VLAN i receive high collision drops and the cpu goes 100% on the switch.

Could anyone please advice on how to configure multicast/igmp for this issue?

vlan 3
ip igmp auto A21,B21

Seems not make any difference.
Honored Contributor

Re: High collision, cluster pool.


What switch is it that you're using?
I've not really worked with anything that uses duplicate MACs in an Active/Active setup so I'm not really sure how the switch would handle it (I'd assume it would broadcast the traffic which may be what you're seeing).
Previous threads I've read suggest it's an issue that's normally solved with the use of a static arp entry but that's not something you can do on the ProCurves.