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Connecting UXIX Servers To Mutiple 6513's

I have a 6513A and a 6513B connected to each other VIA a trunk. I have Windows OS servers connected to each of the 6513's in a active/passive mode on the NIC.

I want to do the same thing for our new UNIX boxes, but everyone tells me this is not possible. The vendor (HP) tells me that I have to go to port aggregation on switch module. I don't want to do that.

Does anyone have any experience in this? I am in the Healthcare industry, and these servers must be up at all times. If they go down, I don't wnat it to be an Infrastructure issue.

Any assistance, and or direction will greatly be appreciated.

Thank you in advance,



Re: Connecting UXIX Servers To Mutiple 6513's

Hello Dave,

Your windows servers are in ALB mode I suppose? In this mode, the NICs balance the TX-load and they use some multicast protocol to sense the availability of the primary adapter. If it fails, the other one takes over and as it works via multicast, the NICs can be on different switches. They only should reside in the same VLAN.

Since quite some time, HP supports port aggregation which is in fact Ether channeling. For an Etherchannel to work, NICs should be on the same device, mostly even on the same board. This is what is recommended to you. To my best knowledge, multi-device Etherchanneling is not yet possible although I have heard from experiments to loosen restrictions on this. Please check the release notes & command ref for your IOS release.

Your best option will be to check in the datasheest if the UNIX boxes support something else than port aggregation. Your vendor may be misinformed about the possibilities but as we do not know the model & type it is not possible to say something about it.