When you place the drives from the "old" filer into the drive bays of the "new filer", I would suggest that you boot from floppy and make sure that the new filer can see all the drives. Since you are using a new "head" ... then you are also going to be using a new NVRAM card. The NVRAM actually puts an entry into the labels of the disks so that the disks know that this data belongs to this filer/NVRAM card. This is just in case there is any leftover data in the NVRAM card before shutdown ...

When you boot, the filer will want to re-write the labels on the new drives placing the new NVRAM card signature onto the raid labels ...

If you boot and all the drives are not seen, some of the labels will be re-written and some will not. You will then have mismatch raid labels and the machine will not boot (too many disks missing from the raid array) ...

You will then need to go in and edit the raid labels (not fun)

So ... the short of all this is to boot from floppy and make sure that the new filer sees ALL the disks

-----Original Message----- From: Jay Soffian [mailto:jay@cimedia.com] Sent: Friday, April 09, 1999 8:33 PM To: toasters@mathworks.com Subject: Swapping disks between shelves (F740 cluster upgrade)

We have an F740 with three FC-AL shelves and 15 9GB disks. The shelves only have a single LRC.

We are getting a new F740 and everything we need in order to setup the two F740's to do CF. The new shelves will have two LRCs as required for CF.

In order to minimize downtime while we are upgrading our current shelves with a second LRC, we'd like to setup the new filer next to the current filer, then swap all of the disks from our current filer into the new shelves. I am assuming that if we do this, when we power up the new filer, it will assume the identity of our current filer.

Then we can upgrade our current shelves at our leisure.

Does this sound like it will work? Are there any compatibility issues between drives and shelves? Any other words of advice about upgrading to CF?

Thanks.

j. -- Jay Soffian jay@cimedia.com UNIX Systems Administrator 404.572.1941 Cox Interactive Media