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New Member

Trouble seeing vhba from UCS on Nexus 5k

I have UCS > 6100(a/b)> nexus 5k (a/b) > emc vnx 5300.  I have two vsans setup and my switch can see both ports on my vnx5300 with show flogi. However, my 5ks do not see the vhba on the ucs system. I have two vhba configured, one for fabric a and one for fabric b. As of now the nexus is connected to the 6100 as a port channel. Port-channel is configred as a trunk. Now this makes me think this is where the vsan communication is failing. Does the connection to the 6100 and nexus need to be something more than a simple trunk?

Dennis

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Cisco Employee

Re: Trouble seeing vhba from UCS on Nexus 5k

Dennis,

I hope you're taking about Fiber Channel uplinks to your N5K and not Eth/FCoE (there's no multihop FCOE yet).

Assuming you have your 6100's with FC trunks to your N5Ks, and the N5K have "npiv" enabled, you should see the flogi from your Host vHBAs.

From the 6100 CLI you can also "connect nxos" and do "show npv flogi" which will show you FC sessions between your 6100 and N5K - which I think is where you problem is.

All your SAN connections would travel over the 6100 Fiber Channel module, up to the N5K Fiber Channel module, then to your array.  You can still trunk and SAN port channel your FC uplinks.  Just confirm this is what you've done and not using Ethernet Uplinks to your N5K expecting that to work.

Can you provide a diagram or detail the exact topology (Eth, FC etc)

Regards,

Robert

17 REPLIES
Cisco Employee

Re: Trouble seeing vhba from UCS on Nexus 5k

Dennis,

I hope you're taking about Fiber Channel uplinks to your N5K and not Eth/FCoE (there's no multihop FCOE yet).

Assuming you have your 6100's with FC trunks to your N5Ks, and the N5K have "npiv" enabled, you should see the flogi from your Host vHBAs.

From the 6100 CLI you can also "connect nxos" and do "show npv flogi" which will show you FC sessions between your 6100 and N5K - which I think is where you problem is.

All your SAN connections would travel over the 6100 Fiber Channel module, up to the N5K Fiber Channel module, then to your array.  You can still trunk and SAN port channel your FC uplinks.  Just confirm this is what you've done and not using Ethernet Uplinks to your N5K expecting that to work.

Can you provide a diagram or detail the exact topology (Eth, FC etc)

Regards,

Robert

New Member

Re: Trouble seeing vhba from UCS on Nexus 5k

Robert you are too quick.

Well the only uplinks between the N5k(a/b) and the 6100(a/b) is a an Ethernet Port-Chan

Nexus A


interface Ethernet1/7
  description UCS Uplink1
  switchport mode trunk
  channel-group 5 mode active

interface Ethernet1/8
  description UCS Uplink1
  switchport mode trunk
  channel-group 5 mode active

interface port-channel5

  description TO UCSA

  switchport mode trunk

Then 6100 side is configured as a Server Port, Mode Trunk, role server.  Am I misshing fiber uplinks between the two?

Dennis

Cisco Employee

Re: Trouble seeing vhba from UCS on Nexus 5k

Bingo.

Between the Host adapter and 6100 is FCoE.  The FC traffic is encapsulate in an FCoE frame and carried on the same wire.  Once it hits the 6100 and goes northbound, it's un-encapsulated and leaves as either pure FC (over the fiber channel uplinks) or via pure Ethernet (leaving one of the ethernet uplink ports).

To use your N5K as your Storage switch, you will need pure FC uplinks between them.  The N5K also must be in FC Switch mode  (rather than NPV). 

There are numerous guides for N5K detailing this.

http://www.cisco.com/en/US/products/ps9670/products_installation_and_configuration_guides_list.html

Regards,

Robert

Cisco Employee

Re: Trouble seeing vhba from UCS on Nexus 5k

A Pic is worth a thousand words.  Here's what your setup would look like. Color coded for uplink type (FC, Eth, FCoE).

A bit sloppy, but here's a quick doodle.

New Member

Re: Trouble seeing vhba from UCS on Nexus 5k

Would it make a difference if they were the 6140xp? 

Cisco Employee

Re: Trouble seeing vhba from UCS on Nexus 5k

No

New Member

Re: Trouble seeing vhba from UCS on Nexus 5k

Okay, so in an enviroment with multiple hops you can only use FCoE over one point? So we can do SAN < fcoe> < nexus> FC< fabric> but not SAN < fcoe> nexus fabric?

Did I also mention that my uplinks to my san are vfc interfaces?

Are all connections from the UCS to the Fabric Interconnects always FCoE?

Cisco Employee

Trouble seeing vhba from UCS on Nexus 5k

Hi Dennis,

Since the UCS Fabric Interconnect currently does NOT support MultiHop FCoE, this is why you are not able to achieve SAN Nexus . There are multihop FCoE topologies that exist such as:

Initial Findings: Evaluating Multi-hop FCoE

Yes, the connections between the UCS Fabric Interconnects and the UCS blades utilize FCoE.

Thanks,

Michael

New Member

Trouble seeing vhba from UCS on Nexus 5k

So I need straight FC to my VNX5300 SAN and between my Nexus and Fabric Interconnects?

Sorry for the 50 questions but i am still learning all of this.

Cisco Employee

Trouble seeing vhba from UCS on Nexus 5k

In short, yes.

A picture says a thousand words. Have a look at the following PDF:

https://communities.cisco.com/docs/DOC-17358

New Member

Trouble seeing vhba from UCS on Nexus 5k

. If your login is unsuccessful, your Cisco.com login does not have the authority level to access this site.

cant access the file

Cisco Employee

Trouble seeing vhba from UCS on Nexus 5k

No problems, here is a screenshot of the relevant details I was trying to highlight. Kudos to Bob Porter for putting this together.

New Member

Re: Trouble seeing vhba from UCS on Nexus 5k

Robert,

Can I leave my  SAN to N5k as FCoE if I have  FC from my 6140xp and N5k? I was told be TAC that the FCoE between the CNA and the FI does not count in the multi-hop FCoE limitations.

Cisco Employee

Re: Trouble seeing vhba from UCS on Nexus 5k

Yes that is fine also.  No multi-FCoE hop so you're ok.  Muti-hop FCoE requires two adjacent FCoE links.  As TAC pointed out you have a pure FC link between the N5K and FI so you're good to go.

Regards,

Robert

New Member

Re: Trouble seeing vhba from UCS on Nexus 5k

Robert,

Sorry to dredge up a closed post but another speed bump just hit me. I added the FC modules to the UCS and the N5k but I can't seem to enable the ports as FC on the N5k. Does this need to be a module for FC to work or can I enable a "Universial Port" for FC?

Dennis

Cisco Employee

Re: Trouble seeing vhba from UCS on Nexus 5k

Which model of N5K do you have?

For 5010/5020 you need a specific FC module.  For 5548/5596 the ports are Universal Ports and need to be configured as FC ports first.

Also confirm:

-You've created the appropriate VSANs on both UCS and N5K

-Assigned the interfaces to the appropriate VSAN on both UCS and N5K

-You're using supported transceivers on either end

Regards,

Robert

New Member

Re: Trouble seeing vhba from UCS on Nexus 5k

Robert, i have the 5548 version. I was able to figure it out after a little troubleshooting. The tac engineer had me going into slot 2 and then the the ports and changing to type FC. I had to go in to slot1. ALl is working now.

My next step is to configure port channels between the A and B paths of N5k and 6140xp. I'll post a new discussion when I can.

Thanks again.

Dennis

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