Ethernet Fabric (VDX, CNA)

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Mel
Contributor
Posts: 63
Registered: ‎10-16-2010

Storage Team Objections to FCoE

Hello -


The server and networking teams in my organozation like the Dell M8428-k/Brocade blade switch. The SAN folks do not. I think their concerns are mostly political - a turf war.


But assuming there are genuine concerns about deploying an FCoE switch, what are they? What TECHNICAL objection could a SAN administrator possibly have to deploying the M8428-k in AG mode? Does anything break? Does the SAN team lose any end-to-end testing capability? Do they lose any management capability? What about failover?


Im trying to understand their concerns more....

Valued Contributor
Posts: 931
Registered: ‎12-30-2009

Re: Storage Team Objections to FCoE

  1. What TECHNICAL objection could a SAN  administrator possibly have to deploying the M8428-k in AG mode?
  2. Does  anything break?
  3. Does the SAN team lose any end-to-end testing  capability?
  4. Do they lose any management capability?
  5. What about failover?

  1. Perhaps they don't (want to) understand FCoE, but the mains issue would be non technical AKA which department is going to manage this device? Is it the network folk or the storage people?
  2. Could be but should not
  3. Depends on what you trying to achive, end-to-end physical is lost, but you didnt have that in a blade env. anyway, end-to-end as infcping and such still work
  4. Depends partly on 1. If we're talking about zoning etc the answer would be no.
  5. For port failover you would need multiple links, a trunk license on both switches is preffered but not neccessary, all port enabled in the blade switch. Then you need to edit the default map of the AG or cable the AG according to the map.
Mel
Contributor
Posts: 63
Registered: ‎10-16-2010

Re: Storage Team Objections to FCoE

Dion, thank you.

Can you please elaborate further on points 3 and 5? As much detail as you can offer will be great! Thanks!

Valued Contributor
Posts: 931
Registered: ‎12-30-2009

Re: Storage Team Objections to FCoE

Point 3 initself depend partly on 1 but in essence should the AG come under management from the Network folk, then the SAN would physically end on the border of the AG and adjecent SAN switch(es). From the AG onwards its in the hands of the Network folk.

Logically the SAN people are still able to test communication with the tooling on their switches, FCPING still works as does ns(cam)show, nodefind etc.

All host behind a AG, appear on the SAN switch on one port (if one ISL is used) as NPIV hosts. Thus NPIV must be enabled and perhaps configured to accept the required number of NPIV host per port and per switch.

Point 5 has to do with how the default map of the AG looks like. AG's map F-ports to N-ports in a particulairy fashion. Perhaps the default map is not suitable in your environment for one or more reasons. Maybe you want Port Grouping or only have one ISL available. Look at the AG admin guide (this is FOS5.3.0 from FS) to get the results you want/need.

Does that make any sense to you?

To add to that:

This is not a technical issue, but has to do with for example who is reponsible for what part of the network.

In the good old days SAN had SAN switches and FC-HBA's to worry about, Network had to deal with everything TCP.

With FCoE whois responsible for the firmware on the switch and or FC_HBA, where is the border between Network and SAN?

Other question or considerations could be, when SAN troubleshooting is required, you need 2 department instead of 1.

And after some time why not go FCoE all the way, even perhaps "how about my job"?

Mel
Contributor
Posts: 63
Registered: ‎10-16-2010

Re: Storage Team Objections to FCoE

Thanks, again, Dion. Sorry for the zillion questions...Im an R&S Ethernet freak by nature.

So, let me a bit more specific. I believe the SAN folks will manage the FOS side of the M8428-k and the LAN folks the Ethernet side.

So, given that, will the SAN folks be able to manage the HBA-component of the CNA (BR1741) as they normally would a vanilla HBA in the world of plain FC?

Would they have visibility to the HBA-component of the CNA and be able to test its performance, look at perrformance statistics, test connectivity, configure it, etc?

And to get even more granular here, is the ability (or lack thereof) to do all of the above a function of running in AG mode or a function of running FCoE?

And switches are run in AG mode all the time, correct? It doesnt have to be an FCoE environment. Its meant to conserve Domain IDs and simplify integration into a non-Brocade SAN.

Lastly, this will be a heavily virtualized ESX environment, so isnt running in AG mode (NPV) a necessity and not a choice - wther FCoE or just FC? How else would all the vHBAs of the VMs perform a FLOGI and get their FCIDs? In other words, the HBA logs in as an N-port and then the VM vHBAs will send out their FLOGIs and the HBA will have to convert them to FDISCs....correct?

Thank you so much!!!

Valued Contributor
Posts: 931
Registered: ‎12-30-2009

Re: Storage Team Objections to FCoE

So, let me a bit more specific. I believe the SAN folks will manage  the FOS side of the M8428-k and the LAN folks the Ethernet side.

So,  given that, will the SAN folks be able to manage the HBA-component of  the CNA (BR1741) as they normally would a vanilla HBA in the world of  plain FC?

FOS is the firmware the switches run on, but i think you ment SAN folk will manage the switch overall and FC specificly with the LAN folk managing the LAN part, yes? If so the SAn folk will be able to do everything i can think of with the CNA. And as it look you got an Brocade CNA its even possible they will manage it from BNA for example.

Would  they have visibility to the HBA-component of the CNA and be able to  test its performance, look at perrformance statistics, test  connectivity, configure it, etc?

Same as above but APM on the switch is lost see below

And  to get even more granular here, is the ability (or lack thereof) to do  all of the above a function of running in AG mode or a function of  running FCoE?

Some things aren't enabled when running in AG mode, but that concerns fabric services which are disabled, zoning, advanced performance monitoring and some other features.

FCoE still uses the fibre channel.protocol only the the FC0 and 1 layers are replaced.

And  switches are run in AG mode all the time, correct? It doesnt have to be  an FCoE environment. Its meant to conserve Domain IDs and simplify  integration into a non-Brocade SAN.

Yes, Yes and Yes. AG is ment as port aggregator and as such needs all port to be licensed, to ease management and to be able to mix in a hetrogeneous SAN without the need for FCR or  Interop modes.

Lastly,  this will be a heavily virtualized ESX environment, so isnt running in  AG mode (NPV) a necessity and not a choice - wther FCoE or just FC? How  else would all the vHBAs of the VMs perform a FLOGI and get their FCIDs?  In other words, the HBA logs in as an N-port and then the VM vHBAs will  send out their FLOGIs and the HBA will have to convert them to  FDISCs....correct?

No, AG is not a necessity. The only requirement for vHBA's is that the switch supports NP(I)V and thats enable on the switch and ports you want to use it on. Whether the switch runs in AG mode or not doesn't matter.

Its the hypervisors responsibility to convert FLOGI's to FDISC and convert the FDISC ACC back to a FLOGI ACC.

 
Mel
Contributor
Posts: 63
Registered: ‎10-16-2010

Re: Storage Team Objections to FCoE

Dion, VERY appreciateive, my friend. Thank you.

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