2014-04-21 11:16 AM
I have 2 RAID DP aggregates with 16 drives each. I want to create a flash pool aggreagate.
I have 4 SSD drives; our vendor suggested to have just one flash pool aggregare with the 4 SSDs (to use 2+2 RAID-DP raid group with no spares) on only 1 controller.
What is best practice for creating flash pool aggreagate? Will it better to create 2 flash pool aggregate one for each controller?
Any suggestions will be a great help
2014-04-22 12:43 AM
It doesn't sound like you have enough drives for 2 flash pools.
For the one that you do have enough drives for I'd make it RAID4 rather than DP. 1+2 and a spare.
You may want to review TR-4070 on Flash Pools.
I hope this response has been helpful to you.
At your service,
Eugene E. Kashpureff
Independent NetApp Consultant, K&H Research http://www.linkedin.com/in/eugenekashpureff
Senior NetApp Instructor, Unitek Education http://www.unitek.com/training/netapp/
(P.S. I appreciate points for helpful or correct answers.)
2014-04-22 02:26 AM
It's worth to mention ONTAP 8.2.x is required to have the ability to configure RAID of SSD pool independently from the rest of the aggregate. If the system is running ONTAP 8.1.x, then it has to be RAID-DP, to follow the existing aggregate config (unless we reconfigure it to RAID-4 too).
In my view it is also debatable whether RAID-4 with a spare is better than RAID-DP with no spares.
2014-04-23 08:05 AM
As Eugene mentioned, TR-4070 is your friend.
Key steps for 7-Mode would be:
option raid.min_spare_count 0
aggr options <aggr_name> hybrid_enabled on
aggr add <aggr_name> -g new -d <disk1> <disk2> <disk3> <disk4>