few questions regarding aggreagates

[igor_stankovic]

Hi everyone,

I am expecting implementation of fas 3160A and 4 disk shelves ds4234, each with 600GB sas HDD, only block access (FC SAN)

System will be configured with ontap 8.0.2

My idea is to assign 2 shelves to filer1 and 2 shelves to filer2

Then i will have 48-3=45 free disks for data on each filer.

First idea is to create 3 aggregates per filer, existing of 15 disks per aggregate (6 aggreagtes total)

But since this is ontap 8.0.2 with support for larger aggregates, i have some ideas

First, on website i checked that 3160 supports maximum 28 disks per aggregate (http://www.netapp.com/us/products/storage-systems/fas3100/fas3100-tech-specs.html). Is this true also with ontap 8.x?

From the link i cannot see ontap version, can i assign more disks per aggregate with 8.x version on this model? And if i can, what do you think of an idea to create 2 large aggregates (one per filer)? I would get more space, but will this overload CPU's and cache on filers?

So i need some advices from your experience : 3x15 disks aggregates per filer, or larger aggregates (ofc if supported - lets say 45 disks aggregate with 2 spares)

Thank you

[igor_stankovic]

one more thing :

from "storage system tehnical faq" guide i have found table as attached

So i think that optimal solution would be to create 1 aggregate per filler consisting of 45 (3 disks are for root vol) disks

in raid dp. Is raid group size of 15 good for this?

Is this OK overall?

[radek_kubka]

Hi,

Actually with 32-bit aggregates (pre-ONTAP 8 & ONTAP 8.x as well), you can have up to 33x 600GB drives in one aggregate. With 64-bit aggregates (ONTAP 8.x), you can have up to 105x 600GB drives in a single aggregate on FAS3160.

This doc explains a lot of detail around RAID group sizes, aggregate limits, spares policies, etc:

https://fieldportal.netapp.com/ci_getfile.asp?method=1&uid=7178&docid=9866

Regards,

Radek

[radek_kubka]

You've almost answered your own question!

There is no need for a dedicated root aggregate in my opinion. You do need, however, spare disks, ideally 2 per controller.

So you are good to go with:

- 45 disks, RG size 15, 3 hot spares per controller

or

- 46 disks, RG size 16, 2 hot spares per controller

[igor_stankovic]

thank you

46 disks size, rg size 16, that will be it