RAID5 limitation to 32 drives

[SAljoshin]

Hello,

We have RSP3MD088F RAID controller with JBODs connected 2x26HDD.

We are unable to add more that 32 driver to build RAID5 or RAID6.

What should we do/use to remove this limitation?!

Regards,

Sergei

[Emeth_O_Intel]

Hi Sergei,

Thank you so much for contacting us about this.

Could you please so kind and provide to me the JBODs model and brand name in order to make sure the information.

Regards,

Emeth O.

Intel Customer Support Technician

Under Contract to Intel Corporation

[SAljoshin]

Hello Emeth,

We are using these JBODs: SuperChassis 847E1C-R1K28JBOD. There is no problems detecting all drives, but creating RAID5 or RAID6. RaidWebConsole says that there is a limitation in 32 drives.

As far as I investigated, there is really limitation in 32 drives in RAID5/6 array and it doesn't depend on controller model. You should use RAID50/60 that has 128 drives limitation.

Sergei.

[Emeth_O_Intel]

Hi Sergei,

Could you please so kind and provide us the link or article where you found the information about this limitation?

Regards,

Emeth O.

Intel Customer Support Technician

Under Contract to Intel Corporation

[SAljoshin]

Hello Emeth,

Few of them are:

https://ask.adaptec.com/app/answers/detail/a_id/17244/related/1

https://www.microsemi.com/product-directory/raid-controllers/4047-raid-levels#12

I don't know is it related to controller or something else, anyway as far as I tested here:

I am able to create RAID50/60 with those 2x26HDD JBOD easily - no problems.

I am not able to create RAID5 or RAID6 with those JBODs. RAID Web Console2 and RWC3 and also RAID card BIOS always says that unable to apply this configuration as it esceeds 32 drives limit.

Latest RAID card BIOS and drivers are installed.

Any solution for this issue or we just have to deal with that?

Sergei

[Emeth_O_Intel]

Hello Sergei,

No problem, thank you so much for the information provided.

I am going to double check those details in order to provide you the most accurate information.

Please provide to me more time and as soon as possible I will get back to you with the next step.

Regards,

Emeth O.

Intel Customer Support Technician

Under Contract to Intel Corporation

[Emeth_O_Intel]

Hello Sergei,

Would it be possible to get screenshots of the error?

Bear in mind that TriMode RAID controllers such as the one you are using should be managed by RWC3 only,

In addition to that, make sure RAID controller is running on the latet FW.

Also, may I know the Brand Name and model of the Server Board you are using?

Regards,

Emeth O.

Intel Customer Support Technician

Under Contract to Intel Corporation

[SAljoshin]

Hello Emeth,

We had so ship these JBOD to customer today already, but i was able to create screenshots for you.

I did 2 methods Simple and Advanced, both in screenshots. As you can see all 52 drives detected. When using Simple method - it automatically takes maximum 32 drives and creates RAID6 array.

When using Advanced method - it shows all 52 drives in a list but when all drives selected "Add Drives" button still inactive. And you can see the sign that tells that RAID6 allows from 3 to 32 drives only.

I didn't have time to do the same in RAID BIOS, but there is the same situation, when all drives selected it says that selected configuration supports upto 32 drives only.

The very first thing we did-was RAID card upgrade - the latest available in download center for it.

1200SPLR board and Xeon 1230v6 CPU

Regards,

Sergei.

[Emeth_O_Intel]

Hi Sergei,

Thank you for the information provided.

I will double check this information and as soon as possible I will get back to you in order to proceed with the next step.

Regards,

Emeth O.

Regards,

Emeth O.

Intel Customer Support Technician

Under Contract to Intel Corporation

[Emeth_O_Intel]

Hi Sergei,

There is a limitation on maximum drives per drive group. It is 32 devices not matter the RAID level.

This is included within the hardware user guide for the Trimode RAID adapters (Section 2.9, Table 5. SAS/SATA drive support limits):

https://www.intel.com/content/dam/support/us/en/documents/server-products/raid-products/TriMode_Adapter_Hardware_User_Guide.pdf

Regards,

Emeth O.

Intel Customer Support Technician

Under Contract to Intel Corporation

[SAljoshin]

Hi Emeth,

Yes I read it also. I believe it is an artificial limit to avoid problem creating bigger number of disks RAID.

Is there any RAID controller that supports more/bigger number of drives in group?

Sergei

[SAljoshin]

Also, take a look at Intel RAID levels description document.

https://www.intel.com/content/dam/support/us/en/documents/server-products/raid-products/SWUG_full_featured_entry_RAID.pdf

Page 18 for RAID5. You may also take a look at other RAID descriptions.That proves that this limitation is artificial to avoid problems in controller work.

Sergei.

[Emeth_O_Intel]

Hi Sergei, Thank you so much for those details provided. Unfortunately, as I mentioned before there is a limitation on maximum drives per drive group of 32 devices no matter the RAID Controller or RAID Level. If you have any other question, please do not hesitate and let me know and I will be more than happy to assist you. Regards, Emeth O. Intel Customer Support Technician Under Contract to Intel Corporation

[Emeth_O_Intel]

Hi Sergei,

I am following up your case in order to make sure if there is anything else I can help you with?

If so, please do not hesitate and contact us back and we will be more than happy to assist you.

Regards,

Emeth O.

Intel Customer Support Technician

Under Contract to Intel Corporation

[SAljoshin]

Hi Emeth,

No, nothing to help with.

Sergei

[Emeth_O_Intel]

Hi Sergei,

Ok, I am going to proceed and close this thread.

If you have any other question, please do not hesitate and contact us back and we will be more than happy to help you.

Regards,

Emeth O.

Intel Customer Support Technician

Under Contract to Intel Corporation