Help me choose FAS 2820 configuration with Disk Shelves

[alessice]

Hi,

We have two FAS 2720 with FlashPool in production configured as follows:

FAS 2720: 4SSD 960GB + 10HDD 4TB
3 x DS212C 12HDD 4TB

We need to increase the available space and I have to decide whether to purchase:

• FAS 2820 with the same disk configuration
• FAS 2820 with the same disk configuration but 4 x DS212C 12HDD 4TB
• FAS 2820 with 4SSD + 10HDD 10TB and 4 x DS212C 12HDD 10TB

We use these FAS via NFSv3 to store our customers' emails (Maildir format, so many small files accessed little but with metadata read very frequently).

With the current configuration, just one of these FAS easily reaches over 22,000 IOPS (data taken from the System Manager Dashboard).

The doubt is:

• if I buy the configuration with 10TB disks and an additional drawer (which costs double compared to the current configuration) will I be able to at least double the IOPS and the occupied space to recover the investment?
• if I buy the configuration with 4 Disk Shelves will I have more space but will I not risk having too many disks (58 4TB HDDs) in a RAID Group with RAID-DP?

With our NetApp sales representative we tried to do some simulations from Fusion of how many IOPS I could reach but according to Fusion the current configuration could not already do the IOPS that it is actually doing.

Can you give me some advice? I would like to send the order soon.

Thanks

[cedric_renauld]

Hello,

A read your use case, and my quesrion is :

Why you dont go on a Flash system ?

You can benefit of dedup ratio and VERY more IOPs, on reduced Rack unit system.

And maybe for the same price ...

You can start with a C30 and 100 TiB, and forgot your IOPs problems

[alessice]

Hi,

I also had our sales representative make me an offer for a C30 with 100TB of space, but the cost is almost double that of a FAS 2820 with the same available space.

[andris · Accepted solution]

Are you sure your FAS2820 is 4xSSD + 10xHDD?  It's a 12-drive chassis, so it's really 4xSSD and 8xHDD.

Anyway, Fusion is conservative, but it is a good tool to estimate performance at a somewhat granular workload configuration level.

You might get some additional advice from the NetApp Discord channel. I recommended joining it and asking your questions there.
https://discord.com/channels/855068651522490400/1062049107096633454

I think there's still headroom in the FAS2820 for another shelf, if you add one.

Don't be concerned over RAID group sizes - the RAID-DP maximum of 28 drives is always enforced. You simply create additional RAID groups to add to the aggregate (or just create new aggregates with the new storage, if you want).