FAS2552 disk partition (ADP) and data aggregates

[maskajan09]

Hello

I'm going to install FAS252 with 4 SSDs and 20 SAS in the base and 24 SAS in the external shelf. As I understand it the ADP is done only on the disks in the base. I want to create only one data aggregate for each node. I see as a good idea not to mix data partiotions from the base and the disks from the shelf. So I would like to create data aggregate for the first node only from the data partitions from the base and the data aggregate for the second node from the disks from the external shelf.

My question is if it is a good idea or if there could be any issues. Is there any better recommendation for this setup?

Thank you

Jan

[AFlowers]

I have setup multiple systems as you have described and it has worked well.  You can also create a storage pool with the SSD and split them between the two aggregates.  Unless you have a specific workload that you need to design against that is the route that i would go.

[maskajan09]

Perfect. Glad to hear that it is ok.

The Flash pool is my second question. I'm affraid that I will always lose 2 disks - DP or r4+spare. Is it correct? Can I go for r4 (3D+1P) for a Flash pool? 

Thank you

Jan

[AFlowers]

You could go R4 (3D+1P) but that depends on your risk tolorance.  Remember that if you loose your storage pool both your aggregates will go offline as well.  I dont think that is a risk worth taking.

[kenji_toyooka]

Need a spare SSD for SSD Storage Pool (FlashPool), so you can configure 1S+2D+1P (R4) or 1S+1D+2P (R6).

Well, I believe following configuration is better ballanced one;

FAS2552A, HDD x44, SSD x4

  Node-1: ADP_Root + [1S+7D+2P] + (1S+9D+2P) + 2AU

  Node-2: ADP_Root + [1S+7D+2P] + (1S+9D+2P) + 2AU

[...] is a RAID group with ADP data partitions.

(...) is a RAID group with phisical disks.

AU is Allocation Unit of SSD Storage Pool.