Should we use FCoe or FC on UCS

[dxb-p]

Hi,

What is the recommended solution for UCS to use FC / FCoE connectivity?

What is the Cisco Validated Design Stand Point?

[balaji.bandi]

Depending on what you have in the bill of material and design, both should work.

check the deployment guide :

https://www.cisco.com/c/en/us/td/docs/unified_computing/ucs/UCS_CVDs/flexpod_datacenter_vmware_netappaffa.html

[dxb-p]

Scenario will be:

Thanks Balaji

FI's will connect to N5K and SAN will Connect to N5K. 

So, what is the best solution? should we use FC / FCoE?

[balaji.bandi]

Depending on the model of 5K, some nexus 5K are modular you can order FC modules and Ethernet Modules.( as I remember it supports - up to 8 physical Fibre Channel uplinks)

Each Fibre Channel port can be used as a downlink (connected to a server) or as an uplink (connected to the data center SAN network) - they are different modes F, NP, E, TE, and SD  (google or cisco site can give you more information).

[Steven Tardy · Accepted solution]

If you use dedicated FCoE links (wires/ports/connections not shared with regular LAN traffic) (I would strongly encourage dedicated links), then there should be little practical difference between FC and FCoE.

FCoE, in theory, would be 10Gbps whereas FC would be 8Gbps.
In practice there would be little measurable difference.

FCoE can be quite finicky regarding QoS, so make sure PFC negotiates on all links.

CSCuh72875 :: FCoE multi-hop performance degraded because of QoS config mismatch

Internally between the UCS Fabric Interconnect and the servers (rack or blade), the traffic is 100% FCoE. But UCS manages all of this configuration to prevent QoS configuration mistakes.