UCS FI-6248 connect to 9504 or 5548?

[gavin han]

currently 5548 is core and FI-6248 connects to Nexus 5548. We have to introduce nexu 9504 as core/spine and connect 5548 to 9504 as access/spine switch. is it better to connect FI-6248 to 9504 or 5548? what's recommended design?

[Walter Dey]

Hi

I assume you have vpc's from the UCS FI to your N5k today ?

Is your N5k doing L2 only ? and if yes, where was your L3 functionality ?

If yes, it means that if you have East-West traffic between different vlan's, traffic has to leave UCS domain, go through a L3 router, and reenter UCS domain. Therefore if the latter is true, you would gain hop count and delay, connecting UCS directly to N9k.

If you have mainly North-South traffic, then connecting to N5k is ok.

[gavin han]

N5K is currently doing routing so we have to introduce N9K as core and move routing N9K. would you recommend moving UCS FI-6248 to N9K from N5K once L3 routing is moved to N9K?

[Walter Dey]

Hi

If you have no or minor East - West inter vlan traffic, connect UCS to N5k; vmotion is intra vlan traffic, and would not need routing.

I think more important is the fact, that all links UCS - N5k - N9k are 10G, and vpc between UCS and N5k, and N5k and N9K.

Network teams might not like direct attachment of end devices to their core boxes.

Walter.