Hey Andrey,
On Wed, Dec 3, 2008 at 1:23 PM, Borzenkov, Andrey Andrey.Borzenkov@fujitsu-siemens.com wrote:
Hi,
We are going to upgrade several filers (FAS270 -> FAS3140). They host FCP LUNs and Windows with MSCS connected. Now what I have been told:
MSCS records disks (LUNs) serial numbers; when these serial numbers change, MSCS won't detect and configure its disks. Basically, cluster has to be recreated from scratch
LUN serial number on filer depends on sysid; when sysid changes, LUN serial number will change
as during head upgrade sysid will change so will serial numbers; so MSCS will be very unhappy.
Is the above correct?
Yes, it all is.
Now we'd rather avoid recreating all MSCS configuration. Are there any pitfalls if we save original serial numbers and set them again on new head before MSCS will go online? Will this work or some more tuning is necessary?
No, that's exactly how we do it :-) Use the 'lun serial' command to reset the LUN serial to the value before the head-upgrade and everyone will be happy.
Greets,
Nils