No sir, that didn't change.
 
Technically, at initial setup, WWN/IQN are based on the NVRAM serial number.  After that, they're stored on disk (I think in the registry), so any head or NVRAM swap will retain the previous WWPN/IQN as long as vol0 and /etc are intact.  This is to avoid people having to reconfigure initiators, zoning, multipathing, volume signatures, etc.
 
So, in general, when you do head swaps and add shelves at the same time, get it working on the original shelves first, then add the new shelves.  If the new head(s) boot with the old and new-from-factory shelves at the same time, the factory shelves will be treated as native, and the original as foreign, you'll end up running setup and get all new WWPN, IQN, etc.
 
I hope this helps clear it up!
 
Thanks
 
Peter

From: Christopher Mende [mailto:Christopher.Mende@peakuptime.com]
Sent: Tuesday, February 24, 2009 11:09 AM
To: Learmonth, Peter; Romeo Theriault; toasters@mathworks.com
Subject: RE: Do fcp/iscsi nodenames change on a cluster head upgrade?

Did the behavior change where the iSCSI nodename is based on the systemid of the head?
 
At best I find you "may" need to rename them:
 
 
From: owner-toasters@mathworks.com [owner-toasters@mathworks.com] On Behalf Of Learmonth, Peter [Peter.Learmonth@netapp.com]
Sent: Tuesday, February 24, 2009 12:55 PM
To: Romeo Theriault; toasters@mathworks.com
Subject: RE: Do fcp/iscsi nodenames change on a cluster head upgrade?

Hi Romeo
1.  iSCSI nodename will not change.
 
2.  FCP nodename will not change.
 
3.  LUN S/N may change depending on the version of ONTAP.  If the LUN S/Ns change, this will affect VMware ESX and any other OS that uses LUN S/N to distinguish paths to LUNs vs. different LUNs.  I recommend you get a list of all LUNs and LUN S/N before the swap (lun show -v), then after the swap, verify and set the LUN S/N to the original value.
filer> lun offline /vol/myvol/mylun
filer> lun serial /vol/myvol/mylun mcDJ8/sjd983
filer> lun online /vol/myvol/mylun
 
This can be scripted.  NetApp PS guys have scripts that do this.  Do you have PS engaged?
 
For more info on the VMware implications, see KB33990
http://now.netapp.com/Knowledgebase/solutionarea.asp?id=kb33990
 
If you redeploy the old heads and set up iSCSI and/or FCP, you should explicitly change them since a new install will generate the same nodename/IQN/WWN/WWPNs.  If they exist on the same SAN/iSAN as the new heads, you will have conflicts.
 
Enjoy!

Peter
From: Romeo Theriault [mailto:romeotheriault@gmail.com]
Sent: Tuesday, February 24, 2009 10:24 AM
To: toasters@mathworks.com
Subject: Do fcp/iscsi nodenames change on a cluster head upgrade?

Hello All, We are in the process of planning for an upgrade of a FAS3050 cluster in single_image cfmode to a FAS3170 cluster which will also be in single_image cfmode. We have a few questions remaining:

 * Do the iscsi nodenames change with a head upgrade? If yes, will this require us to change the iscsi nodename to the old systems for the iscsi clients to be able to seamlessly reconnect to the SAN after the upgrade?

* Does the FCP nodename change with the head upgrade? If yes, will it require us to change it back to the original systems for seamless reconnecting of clients?

* Do the lun serial's change with a head upgrade and does this affect clients in any way?

Thank you for any insight into this.

--
Romeo Theriault
System Administrator
Information Technology Services