I am trying to deliver an attractive and consistent TCO with FAST. My thoughts of best practice with the CX and NS with regard to FAST running flare 30, are to use the same Raid groups for storage pools.
The price of EFD/Solid State drives somtimes prices customers out of solutions.
I would like to use mixed raid groups. For instance at the smallest entry point for my storage pool would look like this.
Tier 1 - EFD - Raid 1/0 or Raid 5(2+1).
During failure in raid 5 using SSD rebuild time is almost nill since the speed of SSD helps rebuild time. Should I have concern with a 2+1 Raid 5?
Tier 2 - SAS Raid 5
300GB, 600GB drives
Tier 3 - NL-SAS Raid 6
2TB Drives, No hot spare on Raid 6
My Question is do I have to use the same Raid groups and Can I use Rais 1/0 at the top Tier 1 and drift towrds Raid 5 Tier 2, and then Raid 6 Tier 3??
What do you all think????
Thanks in advance and look forward to all thoughts.
If you want to use FAST technology, you have to create a storage pool with mixed drive types - meaning that you would have the flash drives, SAS and NL-SAS drives in the same pool. We do not support multiple RAID types in the same pool, so this would mean that you would have the same RAID type for all tiers in your storage pool.
Once you add the requisite amount of drives in the pool, you just have to choose the RAID type for the pool. You do not have to create indiavidual RAID Groups on the drives, the VNX operating environment takes care of that. All you need to do is create a LUN (can be a thick LUN or a thin LUN) in the pool and the FAST algorithm will automatically place the storage chunks on the appropriate storage tier.