Remove mirror from missing disk

[Guest]

I am unable to remove a software mirror from a "missing" disk and receive a
Logical Disk Manager error stating "The requested object is in active use,
operation not allowed". The missing disk was actually a logical disk within a
hardware RAID 5 SCSI array. I have found several articles on the web that
state that the mirror should have been broken first before removing the disk
(or reconfiguring the logical disk on the hardware array in this case). But
what if we didn't break the mirror first? How can I remove the old mirror so
I can re-mirror the data again onto the newly configured logical disk?

I hope someone understands what I'm saying here. If not I'll try and explain
in more detail.

Thanks

 

[wanderer]

You state you are running hardware raid level 5. This is transparent t
the OS and logical disk manager. The OS will only see this as a singl
drive.

Then you mention a software mirror. You could not do this with th
raid5 array. So what other disk was this software mirrored to? Ar
you still showing a software mirror in Disk Manager?

Did you replace the failed/missing disk in the hardware raid5 array???
Is this a three disk raid array


-
wandere

 

[Guest]

OK - time to explain the setup...

The server has 2 array controllers:

Controller 1
Array A = Disk 0 + Disk 1 = Hardware RAID 1
Array B = Disk 2 + Disk 3 + Disk 4 + Disk 5 = Hardware RAID 5
Controller 2
Array A = Disk 0 + Disk 1 = Hardware RAID 1
Array B = Disk 2 + Disk 3 + Disk 4 + Disk 5 = Hardware RAID 5

Controller 1:Array A is software mirrored to Controller 2:Array A (System
(C)
Controller 1:Array B is software mirrored to Controller 2:Array B (Data (D)

This setup provides additional fault tolerance in event of failure of (1) an
array controller (2) external storage array unit (3) two disks failing within
an array. Its complicated I know, but thats the way it is!

The OS Logical Disk Manager gives the following logical disks:
Disk 0 (Controller 1:Array A)
Disk 1 (Controller 1:Array B)
Disk 2 (Controller 2:Array A)
Disk 3 (Controller 2:Array B)
Missing Disk (Controller 2:Array B)

The problem is that Controller 2:Array B was deleted, all disks were removed
and replaced to increase capacity, then a new RAID 5 array created. The OS
sees the new disk correctly but because I didn't break the software mirror
between Controller 1:Array B and Controller 2:Array B I cannot remove the
software mirror and delete the missing disk from Logical Disk Manager.

You are right, the OS should see the hardware arrays as a single disk so if
that is the case we should have a simple situation (forgetting all hardware
arrays):
(1) Disk 0 mirrored to Disk 2
(2) Disk 1 mirrored to Disk 3
(3) Disk 3 was replaced with higher capacity disk without first breaking the
mirror with Disk 1
(4) We cannot now remove the missing disk as it is still part of the mirror
and it won't let us break the mirror because it says the volume is in use.

I've tried the resource kit command line utility with the same results.

Complicated I know but if we forget about the hardware RAID and just
concentrate on the logical disks as above I hope someone can get their head
around this.

Help?!!!!

 

[Bjorn Landemoo]

Dustin

The Win2003 version of Diskpart seems to have a solution, as this MS
Knowledge Base article explains:

http://support.microsoft.com/?id=331494

I'm not sure that the Win2000 version of Diskpart has this function
implemented, though.

Best regards

Bjorn

 

[wanderer]

All that hardware and no hot spares.

So you are doing disk duplexing. In reviewing this ms articl
http://tinyurl.com/22krx

it appears the best approach is to put the original drives back o
controller b and then break the mirror.

This seems strange to me. What would happen if you lost a drive in
mirror set? In NT it was easy to break the mirror with a right clic
and clicking on break mirror.

Optionally you should be able to rebuild the mirror if you replaced th
drive. Is rebuild not a option? You should not have to delete th
mirror to rebuild it but it has been awhile since I used softwar
mirroring extensively. I wonder is the drive size is causing
problem. If you mirror now with the larger disk that has been create
you will have leftover space.


So it looks like two options. The 2003 version of diskpart or put bac
the old disks. Post back what works for you and best of luck


-
wandere