PDA

View Full Version : How do I access dynamic volumes?



Moraxes
03-14-2007, 10:09 AM
Good Morning,
The server at the business my wife owns, running Small Business Server 2003, crashed. We have replaced the hard drive and reloaded the OS. Now a drive she had that had dynamic volumes on it, is inaccessable. You can see the drive in Disk Management, but it states it is a Dynamic Volume but unknown. Is there a way to access these volumes? If not, is there a tool out there that will allow me to get her data from the drive(s)? Any help will be greatly appreciated! Thanks!

Erik
03-14-2007, 04:02 PM
What exactly do you mean? Was it RAID 0 or any other RAID level? How many drives did the server have total?

Paul Komski
03-14-2007, 04:51 PM
It will depend on how the dynamic volumes were configured. If they were in a RAID that included striping (such as a RAID 0) in conjunction with the drive that has been replaced (and we don't know what happened to it) the chances of getting meaningful stuff back is just about zero. Professional recovery of a RAID 0 would require that all drives that were in the array would need to be sent to the recovery firm - and don't expect it to be definitely successful or cheap.

Other configurations should have data that has a good chance of recovery with good software such as GetDataBack (http://www.runtime.org) (for FAT or NTFS as appropriate for the inaccessible file system).

It will cost you nothing to scan the volume with GDB and you might also note that the site also has RAID reconstructor software though all the runtime.org recovery software is dependent on having drives that are at least seen in the BIOS setup.

Moraxes
03-14-2007, 11:04 PM
Thanks for the replies. I guess I did not describe the particulars well enough. Here goes: The boot drive(s) were RAID0 and one of the drives crashed. We replaced both drives and have reinstalled the SBS OS. The drive now in question is a 400 GB drive that was on the primary IDE channel set as a master and was partitioned via the Disk Managment Tool. There were 5 partitions that Windows stated were dynamic. Now we cannot access this drive's partitions. I am assuming that not being a "hard" partition that the OS kept track of the assignments and letters etc, and since the drives that held the OS have been replaced, the new instance of the OS cannot recognize the previously created dynamic partitions. I am sure the data is there but not recognized. I was hoping there was a way to get Windows to see these.

Paul Komski
03-15-2007, 04:54 AM
I am assuming that not being a "hard" partition that the OS kept track of the assignments and letters etc, and since the drives that held the OS have been replaced, the new instance of the OS cannot recognize the previously created dynamic partitions.
Just to clarify a couple of points to avoid confusion. The term dynamic relates only to the drive itself and not to any partitions on it. What is different about the partitions on a dynamic volume (drive) is the way the partitions on it are referenced and not in how each partition is structured. The MBR is non-standard and there are no partition tables as such. The references to what is where on the drive are kept in a "database" which is kept at the end of the physical drive. This is different from the OS itself "keeping track" of what is where - though the OS itself is involved in assigning drive letters and so forth.

From what you say this drive was not involved in any RAID - it was just configured as a dynamic drive. If that is the case then an unknown status relates to a corrupt mbr or other references to the partition geometry.

GetDataBack (http://runtime.org/gdb.htm) should be able to recover from such a situation and it will cost you nothing to run the demo version to see if it can recover your files. It analyses the file systems on the drive and can disregard any partition geometry references. Advise to go this route first and to backup a clone of the drive prior to attempting any other ways of re-initialising the drive.

The reason that recovery will be 'impossible' if it was included in a RAID-0 is that each file is split across all the drives involved in the array - thus you only have one half, or one third, etc of each file available and even their metadata references will be all over the place. If you cant get the stuff back with GDB I would possibly go to a professional recovery firm but if RAID was involved I would suspect this would be a futile exercise.

Some info at http://technet2.microsoft.com/WindowsServer/en/library/bde4b22f-8efa-498f-8647-0c21dd9a403f1033.mspx#BKMK_7 but I still warn against trying to initialise this drive by going the route suggested in the link. It is a way to get a functional drive back but it will be effectively reformatted in the process.

PS and FYI The reason there are two versions of GDB (FAT and NTFS) is that the target drive's partitions need to be scanned for different metadata; FAT TABLES and Directories or an MFT respectively.

Erik
03-15-2007, 09:15 AM
I am getting the feeling that it might have been setup in a RAID 0 array. If that is the case basically your only option will be to send both drives (the one that failed and the original one that works) to a data recovery place. This will be very costly (thousands) to try and recover data with no promises.

This is why backups are very important.

Paul Komski
03-15-2007, 05:28 PM
your only option will be to send both drives (the one that failed and the original one that works)Just be nit-pickity pedantic, one should sent all the drives that were included in a RAID 0, since there can be more than two drives in such an array.

Moraxes
03-26-2007, 01:17 PM
Good Afternoon! Many thanks Paul! We recovered everything using Get Data Back. Only thing we have left to do now is to figure out how to access the .pst file that has the Outlook emails in it.... again many thanks!

Paul Komski
03-26-2007, 03:40 PM
Have replied in your other thread.

http://www.pcguide.com/vb/showpost.php?p=340248&postcount=5