What layer are FI's in the Cisco hierarchical network design model?

[kg6itcraig]

What layer are FI's in the Cisco hierarchical network design model?

Is this a straigh up question? We have a Nexus 7k's for our Core and the FI's Port-Channel to them. So to me they would be Distribution Layer.

But when we attach to Isilon NAS devices we use N3K's between the FI's and N7K's. This would make the N3K's and FI's both part of the Distribution Layer? Would not consider it Access Layer. Yet it does not do ACL's etc that would usually be part of the Distribution Layer. 

Just wondering peoples thoughts on this. Is the UCS FI and "One Off" in the 3 layer model? 

Thanks!

Craig

[Robert Burns · Accepted solution]

FI's can sit at your dist. or access layer.  I have seen deployments where they are deployed at both, depending on the size of the UCS cluster and network bandwidth. The distribution layer is typically be where all the Layer 3 magic happens (routing, ACLs, QoS, FW, policy enforcement etc) and since UCS is strictly Layer 2, it could be classified as an access-layer device. 

Designs are flexible and so long as you account for adqueate over-subscription you should be fine with either deployment option.

Hopefully others will share their insights

Regards,

Robert

[kg6itcraig]

Robert,

Thanks very much. Do believe this is "the answer".

Thanks!

Craig