I have been looking into the Cisco VN-Link technology and it looks pretty good. The only question that I have relates to the traffic from the server to the Nexus 5k. The docs talk of tagging packets so that they can bypass the v1000 and be processed on the 5k. Does anybody know how a 3100 series blade switch would fit into this equation or would it break it?
The VN-Link VNTag implementation is designed to be used with the first physical switch connected to the Hypervisor server.
While the hardware on Nexus 5000 is VNTag ready, the NX-OS software needed to enable the implementation will not be able until the 2nd half of 2009. Around that same time we should also have a Nexus blade switch available that will support the VNTag VN-Link implementation as well.
The Nexus 1000V software implementation will be available sooner with the intial release of VMWare ESX 4.0 - currently targeted for the 1st quarter of 2009.
So, if I were you, I would use the Nexus 1000V on the hypervisor while you have your 3100's. When you upgrade the 3100's to the Nexus blade switch you can consider using the VNTag implementation at that time.
Hope this helps.
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