FC & FCoE on Nexus 5548 & MDS 9700

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Q1: QoS
How good are the default QoS settings for both ethernet & FCoE?

Doing QoS in NXOS is apparently very different from the Catalyst platforms.
I was wondering if we need to specifically change something, or is FCoE traffic automatically placed in a "priority queue", when a port is doing both ethernet & FCoE?

Is there any reason to dedicate a few ports just to do FC/FCoE, or can we put a bunch of ports in a port-channel, and run both ethernet & FCoE over it?
What's the best practice?

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Q2: port-channel load balancing

One customer already tried to run a port-channel between UCS-FI & MDS switch.
He said when you do that, the MDS is NOT capable of putting multiple links into a FC port-channel, to automatically load-balance FC traffic.
That's why he's connecting the UCS northbound to Nexus5548, where a native FC link in a port-channel is then connected to MDS, w/ one extra hop in between UCS & MDS.

Any truth to that?
It's hard to believe MDS cannot do FC port-channel.

Also, I noticed their existing port-channel between N5K & MDS is configured w/ a "channel-group 2 force" command.
In the ethernet world, best practice is to use LACP, or PAgP to negotiate the port-channel.
What's the best practice to form an FC PO in the SAN world?

TIA

Kevin

[Walter Dey]

Hi Kevin

Q1: most of your questions are covered here

http://www.cisco.com/c/en/us/support/docs/switches/nexus-5000-series-switches/116248-configure-fcoe-00.html

Generally: FCoE in the access is state of the art. In the aggregation, people don't like to share Ethernet and FC traffic on the same link; another reason is keeping fabric A / B separation for classical FC (therefore also FCoE); no FCoE traffic over vPC.

Q2:Regarding UCS and MDS; this is of course not true ! it's not E-port E-port trunking channeling, but F-port trunking channeling

Best practise is: UCS in FC End Host Mode (which is the default) and MDS in NPIV mode.

You also have to enable "feature fport-channel-trunk" on MDS

http://www.virtualdatacenter.me/2012/06/fibre-channel-trunking-and-port.html has all the details.

Walter.

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hi Walter,
Thanks for the reply, and the links to useful online docs.

To clarify my customer's comment regarding Q2:
He was able to put multiple ports into a port-channel.

However, when he ran native FC over a port-channel between UCS FI & MDS, there was severe polarization, meaning one link would have much more utilization than the other (assuming a 2-port port-channel).

When he created a port-channel between UCS FI & Nexus 5K, and ran FCoE, he was able to achieve a much better spread across all links in the channel.

Their existing MDS linecards cannot support FCoE, and they didn't test native FC to Nexus, to do an apples-to-apples test, but above is what I was told.
Assuming I summarized the story accurately, is there any reason why he was able to achieve better load-balancing results to a Nexus 5548 via FCoE, than to a MDS 9710 via native FC?

Kevin