FCOE -Basic questions

[ADAman]

My understanding is that the traffic from the blades in the chassis or in a C-series rack contains both FCOE and Ethernet frames.

But what about the traffic from a Netapp UTA? Looking at the NExus switch config, it seems that all ports in use are Ethernet ports. then we configure FCOE ports on top of the Ethernet ports for FCOE traffic. Like this:

interface vfc7
  bind interface Ethernet1/7
  no shutdown

interface vfc8
  bind interface Ethernet1/8
  no shutdown

But what about the traffic coming from the UTA? Does it contain both types and then only one protocol is stripped off on the port? Or what is happening here? My understanding is that a 2-port UTA card can contain 2-ports of both IP and FCOE, ie. 4 ports in total.

Anyone has a paper explaining UTA and FCOE?

[Robert Burns]

Atle,

Traffic type depends on the adapter first & foremost.  The only time a blade/rack server will send FCoE traffic is if there's a CNA installed.  Traditional NICs or HBAs will not generate FCoE.

What your NXOS config is doing is simply creating a virtual FC interface and attaching/binding it to the physical port.  This way when the system receives FCoE traffic, it knows the encapsulated FC traffic belongs to that FC.  Regular ethernet traffic will simply arrive on the physical interface as expected.

My understanding is that the UTA can send either FCoE or Ethernet.  As far as the N5K functions, the UTA operates exactly like a CNA.  On the FCoE side it will be a FC target for block level storage protocols, and on the Ethernet side you can use the same port as a SMB, CIFS, NFS or iSCSI targets for file level storage protocols. All they've done is taken the traditional ethernet ports and FC ports which were historically separate interfaces on the Filer and allowed them to operate as one.  On the NetApp you would still be configuring your traditional FC and IP storage targets, they'd just happen to use the same phsyical interface to communicate with hosts.

Regards,

Robert

[ADAman]

Hi Robert,

I just have one more question on this that still puzzles me: Can the UTA adapter (2 physical ports) be configured with 4 adresses, ie 2 FC and 2 IP-addresses, or is the maxium 2 adresses. The Netapp sees 4 interfaces (2 FC and 2 Ethernet).

2 active adresses is more logical to me, because how will the the other end of the cables, ie. the Nexus switch, be configured ? Can one port on the Nexus switch be configured to receive both FCOE and Ethernet frames? Maybe it can, I am just asking to make this clear.

[Robert Burns · Accepted solution]

The UTA will use both FC and IP addresses concurrently with each port.  It's similar logic to how the N5K operates for the last 5 years.

Yes, a Nexus 5K port can understand both Ethernet & FCoE at the same time.  This is the basis for IO Consolidation with the nexus platform.  On the 5K side, any Ethernet traffic will be received and switched accordingly.  For FCoE, the packets are received, the FCoE packet is de-encapsulated, and the pure FC payload frame within the FCoE packet is then logically received on the VFC interface bound to the N5K physical interface.  The FC traffic is then forward as usual within the switch.

Robert

[ADAman]

ok, thanks, finally cleared up this one.