Possible to put larger disks in LSI arrays?

Question

I have a couple of these LSI arrays

LSI Model: 0834
LSI Class: 3600
LSI Name: LSI Engenio
LSI product name: 1932
LSI Product codename: Mary Jane
Enclosure name: Shea (DM1300)
End of Life: 31-Dec-2010

which was bought with 2TB disks.

My plan is to use either XFS on Linux or ZFS on OmniOS.

Question

If I configure it as a JBOD, I suppose it can put in any larger disk, but what if I use the hw raid? Can I then e.g. replace a failed 2TB disk with a new 3TB, and perhaps even from a different disk vendor and firmware version?

Answer 1

The 0834 line are Fibre Channel disk shelves (ie, they just hold a bunch of disks and aggregate their host interfaces). They take fibre channel disks, not SATA or SAS, and provide a FC interface to one or more host systems (initiators in storage parlance).

Since they're just passing access through they'll support any disk that supports the same physical interface as it provides (eg, if it has 4Gb FC interfaces the disk just has to support the same - most FC devices are backward compatible with a few previous generations of FC).

These systems to not appear to provide hardware RAID capabilities. You would have to find a FC Raid card (I've never seen such an item, but all the requisite technologies exist) or SAN system. Or you could use software RAID.

When you place a larger disk in a RAID than the failed disk it's replacing the extra space is almost always simply wasted. All good RAID systems waste some disk space (a small percentage) to account for variance in capacity between vendors. Playing mix-n-match with disk models, between or within vendors may lead to degraded performance.

Answer 2

Can't answer specifically, but generally installing larger drives into a RAID means they get treated as smaller drives, because all drives in the RAID group need to be the same size.

Some arrays do clever stuff to rebalance, and will notice if you e.g. swap all of them and will let you extend the raid. Some RAID types to 'clever' things, with asymmetric drives. I would not expect an array that went EOL in 2010 to be in this category though.