VNX 5600 Disk Layout Review

Quick observations...

Your EFD layout looks ok to me.

You have used a non best practice drive count for the RAID6 NL-SAS tier (recommended 14+2), shouldn't be a problem as long as it's consistent.

You have no spare for the one of the EFD drive types. Spares are not interchangeable between EFD drive types.

74 NL-SAS works perfect in 6+2R6 config

if i am not mistaken there are only two buses on the 5600, so should be pretty simply to balance.

I appreciate it, guys! You're right on the R6. I'm definitely going to change that to 6+2. I'm actually only going to have 72 NL-SAS since 3 will be hot spares, but the math still works. Also, to clarify, all of the EFD's are the same drive type. I may have miss-typed something in the spreadsheet.

Like I mentioned, I've read through the BP documents, but the other thing I've had trouble finding documented is exactly how the DAE's should be setup as far as Bus & Enclosure numbering. I'd appreciate any opinions on that configuration.

One other thing. I've got 260 600GB SAS disks. If I'm using 9 hot spares & doing R5 (4+1), that leaves 1 additional disk. What would be the best way to incorporate that disk? I could make it a hot spare, but that seems like a waste however I may not have a choice.

can't do much with one disk, an extra hot spare can't hurt. One less HS to purchase the next time around.

Hmm...I wasn't aware there was a different drive type within the 200GB EFD's. I found another thread saying that FLV42S6F-200 is SLC FLASH while V4-2S6FX-200 is eMLC, therefore they aren't the same drives. That being said I'm guessing best practice would be to have a hot spare for each type. Good catch,guys.

So, my question now is, will a hot spare work...at least temporarily. For example, a eMLC drive fails, will the SLC drive at least hot spare long enough for a replacement or will it not hot spare at all?

Clayton wrote: I appreciate it, guys! You're right on the R6. I'm definitely going to change that to 6+2. I'm actually only going to have 72 NL-SAS since 3 will be hot spares, but the math still works. Also, to clarify, all of the EFD's are the same drive type. I may have miss-typed something in the spreadsheet.

Good call on the 6+2 RAID6.  You lose a lot of capacity to parity though but that just a consequence of the architecture. There's always trade-offs.

I may still go with R6 14+2 vs 6+2 to increase overall usable capacity. We'll see...

think about rebuild times on big drives, chances of multiple failures. If this was a dedicated R6 pool for some deep archive data / backups, i would try to squeeze as much usable capacity as possible. This is going to be part of FAST right ? One private RG goes, entire pool goes.  That's just my opinion

I suppose it depends on whether all that capacity is required or not. perhaps it can be split out ?

Clayton knows the requirements though, so which direction is chosen will depend on that, and the risk appetite.

All excellent points. I appreciate the feedback!