Virtual Disk Degraded

Question

There is a physical DC with a Raid 1 Mirror, 2 Physical Disks, 500GB each. Dell Server Administrator is installed on the DC, and is reporting both physical disks are fine, online, in a good state etc. On a PERC S300 Raid Controller:

Physical Disk 0:0 Physical Disk 0:1

However at the same time it's reporting that a virtual disk is degraded, what exactly does this mean? The virtual disk indicates it's State is in a Raid 1 Layout. Device Name: Windows Disk 0

If my understanding is correct then the Virtual Disk, when you drill down into Dell OpenManage should have both physical disks as members, as it is a mirror? Is this correct? However, when I drill down into the Virtual Disk, it only displays Physical Disk 0:0 included in Virtual Disk 1.

I'm very new to server side/raid management etc. just while our server techy is away!

Thanks!

Solution

RAID 1 is a mirror. The fact that when you drill down into the virtual disk, you only see Physical Disk 0:0 means that Disk 0:1 has failed and is showing as removed.

You could try removing the faulty disk (should be showing with an orange light) and re-inserting it - this sometimes kicks off a rebuild but even if that works you should probably consider replacing the drive to be on the safe side.

If the drive needs replacing, check if you have pro support on that server before you go buying anything - Dell will send you a new one for free if you have, but they'll probably ask you to do a DSET report first.

It's unusual for the Dell OMSA console to show a RAID virtual disk as degraded but the physical disks as not having any problems. Try refreshing the physical disk status to see if anything changes.

EDIT: From the hardware log you posted, it does look like disk 0:1 failed and then came back online. Normally, if OMSA thinks the hardware looks OK, this would let you initiate a rebuild of the array. You might want to try this but I would expect the disk to fail again before long.

Comments

[PnP]

How do you refresh the physical disk status? and many thanks your reply, do you have much experience with Dell OpenManage?

[Chris McKeown]

Depends on the version of OMSA, but at the top of the screen you might see a circular arrow button that you can click. On the physical server itself, is one of the drives flashing an orange light?

[PnP]

Tried refresh which made no difference, in terms of the disks, this is remote work as of now, will be heading there in a couple of days - the two drives, 0:0 and 0:1. 0:0 is checking in as Online, where as 0:1 is showing Ready. Also, if I drill down, 0:0 has all 465GB of disk space used, whereas 0:1 has only 0.5GB of the 465GB, so I assume the mirror must of broken?

[Chris McKeown]

It suggests to me that the mirror was never created in the first place - are you sure this has happened recently?

[PnP]

Yep - it has, we use Kaseya and it has only just flagged the alert.

[Chris McKeown]

Have a look in the hardware log section of OMSA - it might tell you which disk in the virtual group went offline. If it is disk 0:1 then it's very odd that it's showing as online with no space used - if the drive had come back online it should have initiated a rebuild. Are there any other virtual disks on the controller?

[PnP]

Please see the screenshot now attached to the original post - and again, many thanks for your assistance.

[Chris McKeown]

Answer edited accordingly.

[PnP]

How can you initiate a rebuild? I'm digging around OSMA now and can't find any options for such?

[Chris McKeown]

It should really initiate the rebuild automatically if the disk has come back online. If there is an available disk to rebuild the array, there should be a rebuild option in the available tasks dropdown for the array. I strongly suspect that you'll need a new disk though.

[PnP]

Under the 'Virtual Disk 1' Tasks or the Tasks dropdown for the Physical Disk 0:0 and 0:1 Menus? Either way, neither one has a rebuild option, just assign hot spare.

[Chris McKeown]

In that case OMSA doesn't think there's a disk you can use to rebuild the array with. Replacement time, I think!

[PnP]

Right, Thanks again Chris, all the help is much appreciated!