MSA2040 Hardware Reorganization

[Lekhpal]

Hello All. We've an MSA20240 with a total of 3 enclosures and each has 12 drives. As usual it had two Pools A/B. A on Enc1 with 12 drisk, and B on Enc2/Enc3 with 24 disks. Once we delete PoolB entirely, what is the procedure to remove its two enclosures as those will be not in use. What it entails on hardware part or the cabling part, if we have to completely get rid of two enclosures.  Can MSA2040 runs on single controller.  Please advise.  Best

[ArunKKR]

Hi, 

After deleting Pool B (using delete Pools B command) all the disks in enclosure 2 and 3 will appear in available state. You could shut down storage controller A (using the command shutdown A), remove the SAS back end cabling between MSA controller A and disk enclosures in controller A path, restart storage controller A (using the command restart sc A),  shut down storage controller B (using the command shutdown B), remove the SAS back end cabling between MSA controller B and disk enclosures in controller B path and restart storage controller B (using the command restart sc B).

Power to disk enclosure could be removed and it could be removed from the rack.

MSA 2040 would work in single controller mode.
However, I would advise against removing controller B as array will not have controller level redundancy.
MSA 2040 is an end of support life hardware. 
Controller B will kick in when controller A crashes or fails completely.

Controller B will also be useful when all paths from controller A to host servers fails.

[Lekhpal]

Hi Arun.  Thanks for the details.

So, in such a case, how can we remove the two disk enclosures(related to Pool B) and without missing Controller B as well. Any guidelines and steps for that part.  Basically, we keep the two controllers and only get rid of the two disk enclosures.  BR.

[ArunKKR]

Hi Lekhpal,

The steps that I have shared earlier is for disk enclosure removal as well as retaining controller B in the array.

[Lekhpal]

Hi.  If I see the sequence given by you.  We would like to know, in which step we are going to remove only the disk enclosures related to Pool B(or controller B?).  We don't want to remove the disk enclosure related to Pool A(Controller A?). From the steps it looks like we are removing the disk enclosures in the path of Contoller A as well .That is not what we want to do. We only want to remove the two disk enclosures which got free after the Pool B was deleted.  Please provide assitance on this ask. Thanks.

[ArunKKR · Accepted solution]

Hi,  MSA 2040 controller enclosure 1 holds the controller A , controller B and disk drives in it.
Controller A and B have back end SAS ports to connect to disk enclosures.
Disk enclosures have IO module A, IO module B and disks in it.
Controller A back end SAS path refers to cabling from controller A back end SAS port to disk enclosure 2 IO module A and  from disk enclosure 2 IO module A out port to enclosure 3 IO module A in port.
Controller B back end SAS path refers to cabling from controller B back end SAS port to disk enclosure 2 IO module B and  from disk enclosure 2 IO module B out port to enclosure 3 IO module B in port.

Cabling might slightly differ based on whether you are using fault tolerant cabling or straight through cabling.

Refer to images in the below advisory related to MSA 2040 cabling:

https://support.hpe.com/hpesc/public/docDisplay?docId=c03823462&docLocale=en_US

Controller A and B has paths to all the disks in the controller enclosure 1.

As per your initial description Pool A is created using only disks in controller enclosure 1.
Pool B is created using only disks in disk enclosures 2 and 3.
If this information is correct the steps that I have shared holds good.