Highlighted
JimConnolly
1 Copper

Storage group guidance

Jump to solution

Hi all,

We are in the process of expanding our storage environment and wanted some guidance on configuring our group/pools.

We currently have storage group consisting of one 12TB PS4000E, this is used as mass storage for file servers and mail archiving. All volumes reside in the default storage pool.

We have purchased a 24TB PS4100E and a 14TB PS6100X to add to this group. The idea is to migrate the current file server/mail vault data away from the PS4000E so it can be removed from the group and utilized elsewhere in the business.

In scenario 1 we add both devices to the group and into separate storage pools and migrate the volumes from the default storage pool to the pool containing the PS4100E. Then remove the PS4000E from the group.

In scenario 2 we have the PS4100E and PS6100X in the same storage pool and migrate the data over in the same manner. The group can then distribute the data as it sees fit.

In future we will be migrating VM storage over from another group, containing one PS5000.

What are the pool and raid level considerations for these scenarios? Raid5 has been recommended for both of the new devices but can they coexist in the same pool and work well with the same raid level?

Thanks in advance.

Jim

0 Kudos
1 Solution

Accepted Solutions
Moderator
Moderator

Re: Storage group guidance

Jump to solution

Yes, you can run different RAID levels in the same pool and across different spindle speeds with the when using the latest version of the firmware (v5.x and v6.x).

So you can add the new members in any combination you like (one a R10 or both R10, or both R6, or just one as a R6).  APLB (Automatic Performance Load Balancing) will look at various aspects of the IO, disk speed, RAID type and determine the best placement for the volume slices and move data as needed (in the background) to provide the best performance.

Just note that because SAS arrays typically have more space, volumes will typically have more slices on the larger capacity array.

-joe

-Joe

Social Media and Community Professional
#IWork4Dell
Get Support on Twitter - @dellcarespro

Follow me on Twitter: @joesatdell 

3 Replies
Moderator
Moderator

Re: Storage group guidance

Jump to solution

Either scenarios will work however, to get the best benefits, you may consider a different RAID Policy based on application IO and performance load balancing first.

You mentioned RAID5 however you may want to rethink that (see below links).

You should take a look at the RAID Consideration and Load Balancing Documents to get an idea of the benefits of mixing members with different RAID policies in the same pool.

Load Balancing

www.dellstorage.com/.../DownloadAsset.aspx

RAID Best Practices:

en.community.dell.com/.../new-equallogic-raid-tech-report-considerations-and-best-practices-released...

Regarding Raid5:

RAID 5 and RAID 50 have historically been attractive options, they no longer offer adequate data protection in many environments.  RAID 6 and RAID 10 offer significantly higher levels of resiliency with very high capacity drives

-Joe

Social Media and Community Professional
#IWork4Dell
Get Support on Twitter - @dellcarespro

Follow me on Twitter: @joesatdell 

0 Kudos
JimConnolly
1 Copper

Re: Storage group guidance

Jump to solution

Hi Joe,

Thanks for the response. I understand the recommendation for raid 6/10 and will definitely take this on-board.

I have read through the article and document but I still have one question: would Dell recommend that we run differing raid levels on these 2 members assuming they reside in the same pool? As these devices are running 7.2k and 10k drives respectively can we run raid 6 on both and have the pool efficiently distribute the volumes or would it be best practice to run raid 6 on the 4100E and raid 10 on the 6100X? I believe we will have sufficient performance from the 6100X with either raid policy and raid 6 seems the more attractive choice. I guess the drawback would be that we could not 'lock' a volume to a member by defining its raid preference?

0 Kudos
Moderator
Moderator

Re: Storage group guidance

Jump to solution

Yes, you can run different RAID levels in the same pool and across different spindle speeds with the when using the latest version of the firmware (v5.x and v6.x).

So you can add the new members in any combination you like (one a R10 or both R10, or both R6, or just one as a R6).  APLB (Automatic Performance Load Balancing) will look at various aspects of the IO, disk speed, RAID type and determine the best placement for the volume slices and move data as needed (in the background) to provide the best performance.

Just note that because SAS arrays typically have more space, volumes will typically have more slices on the larger capacity array.

-joe

-Joe

Social Media and Community Professional
#IWork4Dell
Get Support on Twitter - @dellcarespro

Follow me on Twitter: @joesatdell