Regarding spanning RGs on multiple shelves, I've read on several other forum posts to avoid doing that due to degraded performance.
If an 8/14 RG split is really that bad I'll work on getting that corrected today. It won't be an issue at all, just time consuming.
According to this document:
http://www.netapp.com/us/products/storage-systems/fas2200/fas2200-tech-specs.aspx
I can have a maximum of 20 disks per RG (18 +2 for parity) and a max of 120TB for my aggregate.
From what I'm reading, this seems to be the preferred method:
Filer, Shelf 1, and Shelf 2 = RG of 9+2, and 10+2 = 23 disks and 1 hot spare per storage node
Total of roughly 57 TB after RAID penalty, etc. and 3 hot spares
Or
Filer = 2 RGs of 10+2 = 24 disks
Shelf 1 = 2 RGs of 10+2 = 24 disks
Shelf 2 = 2 RGs of 9+2 = 22 disks
Total of roughly 58 TB after RAID penalty, etc. and 2 hot spares
I think I'm going to go with Option 2 since I have 4-hour support on these.
I've read that going past 14 disks per RG actually hurts performance, even though you have more spindles.
Do you see anything I'm missing?