remove drive from array and assign as hot spare

Hello Rwood56847,

The way you are suggesting will work.  However, there are a few things that you will need to be aware of.  First is that in doing this you will lose a disks worth of space and I/O.  Also, your entire raid will need to restripe which can take some time. I also have seen that in some cases when a customer does a shrink like this that they can get lost pages that need to be manually audit to fix. If you are not experienced in doing audits on a Compellent system’s then I would suggest that you contact support for assistance in this. 

Please let us know if you have any other questions.

Hi Sam,

Even though this post is older but I am in a same boat as previous writter. 

I did exactly the same as he described, but the disks released are sitting in Unassigned folder and I can't see any other option to assign them as spare. I did rebalance the RAID as well but no avail.

My system is SC4020 though.

Can you please let me know how we can achieve this? I want to assign two disks as spare.

Thanks.

Hello @MarkiB,

Managing unassigned disks means moving the disk to a managed disk folder. Normally, there are two ways to solve this kinf of issue. First on the GUI and second running certain commands over serial connection.

You can try with the GUI, but some times it is simply just not possible to do it on the GUI. In this Storage Manager 2020 R1 Administrator's Guide https://dell.to/3so8jsc you can find some usefull information (just look for "unassigned" and you will see ow the process can be done).

However, if you tried this options and you are still not able to assign the disks you will need the commands option and this is normally done by Compellent support. You can try to check the forum for more information like this one: https://dell.to/37MTfuM but maybe you will try to contact Support to perform this operation.

Regards.

Can you check your SCOS Version? I ask because with 7.3 they introduced the "distributed spare" feature.

@DiegoLopez I don't have any issue with moving the disk to a managed disk folder. I can move it managed disk folder but I want to make the released and unmanaged disk a hot spare. 

I went through the guide and it doesn't talk about how to make unmanaged disk a hot spare.

@Origin3k the SCOS version is 7.3.11.28.

Is the distributed spare managed by compellent by itself of we need to do something?

If you upgrade to 7.3 and beyond DSM will ask a question about to enable the Distributed Spare optimizer. You can modify this setting under (right klick) Editing SC  -> Storage. You can also see it if you take a look to all of your disks and with the enable Spare Optimizer you havent empty disks any more and instead on most when not on every one the SCOS will reserve a spare portion.

SCOS have reserve the space of 2 10K (1.8 and 2.4TB) disks and one for SSD.

Does the storage type a configures for single or dual redundancy?

Regards,
Joerg

Now I got it.

Thanks for explaining. Yes, "Distributed Spare Optimizer Enabled" is ticked. 

And storage type is "dual redundancy". 

It means the compellent will automatically take care of spare thingy in disk failure situation?

Regards,

Mark

So with dual redundancy you will survive a double disk failure. Data will be stored like RAID6 and RAID10-DM.

Yes the SCOS will handling the spare drive capacity and it will be kicks in automatically as soon as a drive will fail.

Regards,
Joerg

Also the amount of (hot) spare capacity will take into account how many disks you have an how the spread over exiting enclosures.

In a SC with 31x 1.92TB SSD and ~80x 1.8TB 10K (in 4 enclosures) i have around 13 or 15TB of (hot) spare capacity in total.

So depending on the number of disks in your SC you may already have multiple (hot) spares. I dont know how current SCOS 7.x handle the amount if spare capacity exactly but back in the old days it counts like

1. Spare per Disktype per Enclosure
2. Every 21th. a additional Spare

Regards,
Joerg

As always, Thanks.