HP APA Load Balancing and Cisco 2950 switch

[B. Jen]

I am trying to setup the load balancing between the rp3440 and Cisco Catalyst 2950 switch. Should I use the dst-mac or src-mac on the Cisco switch.

Thank you in advanced for answers.

[Ronaldinho]

Hi Bernard,
I can't answer your question but I am curious if you figured out which is best?

Regards,
John

[B. Jen]

Hi John,

I think once you setup the load-balance, the default is SRC-DST. I changed it to DST-MAC. I can't tell any differences.

Bernard

[Ronaldinho]

Thanks Bernard

[Frank Benke_1]

the load balancing is done on an hash value that is built on the source and destination mac address. if you select the source mac on the 2950 the switch answers with one mac address in the entire VLAN and does not distinguish single ports. source and destination refers to point to point connections so the incomming traffic from other systems is allready otherwise load balanced.

so the only efect you might achive is by selecting the destination mac.

regarding the hash algorithms which basically consider the mac values and the fact that the mac values on the rp3440 are close together, you likely end up in a not so nice hash characteristics.

one thing that you might do to "finetune" the balancing is change one of the nics to another product charge and dont use tandem cards for loadbalancing. more hackish is firmware tuning for "software loadable" mac addresses. but I don't know how HP-UX works with that.