topic Global SP in MSA Storage

Global SP

eXPlosion_ — Wed, 24 Jan 2018 16:32:22 GMT

One disk failed in our MSA, this was a notice that reconstruction started:

a spare disk was used in a vdisk to bring it back to a fault-tolerant state

we have enclosures 1 and 2, this is the second enclosure:

The first enclosue has all 12 disks as VDISK. So it basically means that we have 24 disks and one GLOBAL SP.
In other storage we have 24 disks and 2 VDISK SP.
So if the disk in first enclosure fails will GLOBAL SP kicks in from enclosure 2? And VDISK SP if for local enclosure only?

Re: Global SP

Torsten. — Wed, 24 Jan 2018 16:37:28 GMT

a vdisk SP is for this vdisk only, a global spare can be used for every vdisk (as long as the specs fit the vdisk).

Re: Global SP

Shaan_M — Mon, 23 Apr 2018 15:21:52 GMT

Hello,

Disk Spare should kick in irrespective of the enclosures,

However if it is a dedicated VDisk Spare, It'll kick in only if there is HDD Failure in the designated VDisk and will ot be a part of any VDIsk.

If set as Global Spare, Will kick in , in the event of failure of HDD in any VDisk , Provided the drive meets the parameters of the vdisk.

Hope this clarifies the query.

Regards

Shaan

Re: Global SP

Shawn_K — Mon, 23 Apr 2018 16:37:30 GMT

Hello,

There is a firmware algorythm that helps determine which spare is picked up first. As mentioned, if a vdisk has a dedicated spare that will be the first drive pulled in for a rebuild. If you have two enclosures where each enclosure has 11 drives in a vdisk (vd01 and vd02 for example) and the remaining drive in each enclosure is set as a Global Spare, then if a drive fails in the first enclosure, vd01, the global spare in the first enclosure will be picked up for the rebuild as long as it is the right capacity.

If the global spare is not the right size or type then the global spare in the second enclosure will be used as a the reconstruction target.

Cheers,
Shawn