MSA2052 + 2 additional shelves Pool setup

[m8x]

Hi, 

we use the storage to host a lot of VMs.

Currently we have the following setup:

MSA2052 configured with only Pool A

1x Raid 10 disk group #1 with 16 SAS drives

1x Raid 10 disk group #2 with 4 SAS drives

1x SSD performance tier Raid 1 with 2 SSD drives

2x global hotspares

1 Volume using the above setup

We bought two expansion shelves with 14 SAS drives and 2 SSD drives each.

How should it be set up? I was assuming to do the following:

- Delete performance tier Raid 1 and recreate it with all 6 SSDs using Raid 5.

- Create additional Raid10 disk group #3 with 7 SAS drives of shelf 2 and 7 SAS drives of shelf 3 = total 14 SAS drives - all in POOL A (does striping the group over both selves makes sense at this point?)

- Create additional Raid10 disk group #4 with 7 SAS drives of shelf 2 and 7 SAS drives of shelf 3 = total 14 SAS drives - all in POOL A (does striping the group over both selves makes sense at this point?)

- expand existing Volume to new maximum size

Will this work? Is there a better (more performing) option possible? I am also not sure if putting some groups in Pool B will work as we want to use only one big Volume for everything to gain performance from all the disks.

Any recommendation is much appreciated.

Thanks

[Raghu_A1]

Hello,

It is always recommended to follow the best practices for provisioning storage on the MSA. Please refer pages: 12 to 26 in the following link:

https://h20195.www2.hpe.com/v2/getdocument.aspx?docname=a00015961enw

Thanks & Regards,

Raghu A

[SUBHAJIT KHANBARMAN_1]

I would suggest to dissolve everything after taking data backup. Then consider resetup.

There are total 50 SAS drives and 6 SSD drives

I understand you look for only 1 volume so all drives need to be part of same Pool

You need to keep in mind that at the time of creation of all disk groups in a tier with the same RAID type and number
of drives to ensure uniform performance in the tier. So your existing setup not at all recommended.

You can consider creating two 24 SAS drives RAID6 Virtual Disk groups and keep 2 Global spares but you need to make sure in future if you want to add more VDG in this Pool with SAS drives then you need to create again 24 drives RAID6 VDG only. This is also meeting "Power of 2" for the data drives.

Otherwise you can create three 16 SAS drives RAID6 Virtual Disk groups and keep 2 Global spares.

Otherwise you can create four 12 drives RAID6 Virtual DIsk groups and Keep 2 Global spares

There are multiple options possible which you can think of

Regarding SSD drives you can create one 5 drives RAID5 Virtual Disk Group to meet "Power of 2" for the data drives and keep 1 SSD drive as Global spare

All Part of one Pool and then create 1 volume as per your requirement.

I hope you have full license so that you can get the benifit of Automated Tiering otherwise above setup not possible.

Hope this helps!
Regards
Subhajit

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[m8x]

Hi Raghu, hi Subhajit,

yes, I have a 2052 licensed.

Thank you both for your reply. I checked the guide and I rethought about the future setup.

So in fact (if I got that right), it would make more sense to balance between both controllers, so I could think of having 2 Volumes then.

Is there a reason why I should use Raid6 instead of Raid10? Losing capacity is not an issue for us. Performance is more important.

Thinking of two Volumes in 2 pools now - possible options:

Option 1 (two symmetric Pools): Pool A -> 2*12 SAS Disks Raid 10 + 3*SSD Tier Raid5 /|||\ Pool B -> 2*12 SAS Disks Raid 10 + 3*SSD Tier Raid 5 /|||\ 2* Global Spares

Option 2 (two asymmetric pools): Pool A -> 2*16 SAS Disks Raid 10 + 4*SSD Tier Raid5 /|||\ Pool B -> 1*16 SAS Disks Raid 10 + 2*SSD Tier Raid 1 /|||\ 2* Global Spares

At the moment I prefer option 2 as this offers the possibility to distribute different types of VMs to the two different Volumes. Also It would be easy to add another volume group later with another 1*16 disks to Pool B. From my perspective there is no need for us for any SSD spare.

What do you think?

Thanks

[Shawn_K]

Hello m8x,

I prefer option 2 as well. Balancing load across your controllers will not only allow you full use of the array but having two pools also opens up future expansion options for you.

Personally, I do not like (or advise) to put everything into a single volume. That limits possible options as your needs expands and also gets you into a single point of failure.

Cheers,
Shawn

I work for Hewlett Packard Enterprise. The comments in this post are my own and do not represent an official reply from HPE. No warranty or guarantees of any kind are expressed in my reply.

[SUBHAJIT KHANBARMAN_1 · Accepted solution]

Those are just examples I have shown but yes to get max performance you should go for RAID10

For me Option 1 looks fine.

I would like to correct Option 2 only at the SSD portion because you need to consider "power of 2" for data,

Option 1 (two symmetric Pools): Pool A -> 2*12 SAS Disks Raid 10 + 3*SSD Tier Raid5 /|||\ Pool B -> 2*12 SAS Disks Raid 10 + 3*SSD Tier Raid 5 /|||\ 2* Global Spares

Option 2 (two asymmetric pools): Pool A -> 2*16 SAS Disks Raid 10 + 3*SSD Tier Raid5 /|||\ Pool B -> 1*16 SAS Disks Raid 10 + 3*SSD Tier Raid5 /|||\ 2* Global Spares

Now you need to decide as per your business requirement and future needs.

Hope this helps!
Regards
Subhajit

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[SUBHAJIT KHANBARMAN_1]

Hello @m8x

Request you to kindly let us know the option you went or planning to go.

If you are satisfied with answers out of this forum then kindly mark it as resolved so that everyone who are following this can get the update properly.

Hope this helps!
Regards
Subhajit

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[m8x]

Thank you Shawn and Subhajit.

Sorry, I was not working over the weekend so I started configuration today.

I went for Option 2 with a big Pool A and a smaller Pool B, both having the 3xSSD Raid 5.

Now we have the option to expand Pool B later on and also the ability to add 2 more SSDs and recreate the two Tier sets Raid 5 to expand to 4 drives each, if needed.

We also decided to not have one big Volume in each Pool but having now several small Volumes instead, so we can calculate better and also distribute our VMs better.

Thanks again!

m8x