3800GB SSDs aggregate design

[Joao_Matos]

Hi,

We're purchasing new SSDs and having a FAS8200 with 1x12 3800GB SSD aggregate what is the recommended practice when adding 12 disks more?
Is there any kind of performance limitation on having 1x23 (1 spare) raid group and aggregate with 3800 SSDs?

Or should I create a second aggregate and lose disks space due to parity?  

I'm afraid there could be a controller limitation with larger SSDs aggregate.

Many thanks for the advices!

[SpindleNinja]

There are limits,   check hwu.netapp.com for details.   (And your controller will bottleneck before the SSDs will, that was more a concern with spinning disks.) 

What's your current RAID/aggr config like?    Sounds like you only have 1 aggr assigned to one of the controllers? 

[Joao_Matos]

Hi,

Thanks for the reply!
On this controller node we have 2 Aggregates.

1x11 3800GB SSD Aggregate  1 RG.

1x108 900GB SAS Aggregate with 4 RGs of 27 disks + 1 RG of 8 SSD for Cache

[SpindleNinja]

Couple more questions for you. 

Each controller has an aggr then, correct? 

Which disks have ADP configured / where are the root volumes? 

[Joao_Matos]

Sorry yes indeed. 
This HA pair has 1 root aggregate per controller.

Each of these aggregates is composed by 1 RG of 3 900GB SAS disks. They contain the root volumes. 

The 12 new disks are to be added to the single SSD shelf with the existing disks assigned to the concerned controller.

[SpindleNinja · Accepted solution]

Sounds like the 3.8's are out on their own, in that case I would just add those 3.8s to the same aggr and configure it in just a single raid group.   You'll get the most capacity that way.  

Give this a read over. https://docs.netapp.com/ontap-9/index.jsp?topic=%2Fcom.netapp.doc.dot-cm-psmg%2FGUID-EE30CDA9-095F-4DD1-9A29-BB9F0E55DB4F.html&cp=2_7_7_2