RAID 0, accidentally changed to AHCI in bios - Can I recover?

#1
I have a Dell XPS 8300 personal comp with a RAID 0 on two physical 500GB drives.
The machine booted to black screen with blinking white cursor this morning; no access to F8 menu.
It only had access to F2, and the F12 Dell diagnositics.
A look at the bios settings showed that the drives were set to AHCI.
I switched back to RAID and now the system boots to the DRMK v8.0 prompt (whatever that is...)
I can't seem to get beyond that. Still can't get to the F8 boot menu.
Anyway to recover the data on the RAID 0 and boot to Windows 7 again?
I tried a recovery CD made on an identical comp but when it boots there is no OS in the list.

Ty!
 

mqudsi

Mostly Harmless
Staff member
#2
Grab a Linux live CD, install mdadm raid tool, cross your fingers, and try to rebuild.
 
#3
Ok, forgive me, but I need a little assistance with this. It sounds reasonable and I'll give it a try but I'm stuck.
I got an iso for Ubuntu and burned a cd.
I used this one: http://old-releases.ubuntu.com/releases/6.10/ first link.

I booted to it, but I'm not sure where or how to install mdadm. I'm not very familiar with Linux.

Ty!


Grab a Linux live CD, install mdadm raid tool, cross your fingers, and try to rebuild.
Addendum

Ok, forgive me, but I need a little assistance with this. It sounds reasonable and I'll give it a try but I'm stuck.
I got an iso for Ubuntu and burned a cd.
I used this one: http://old-releases.ubuntu.com/releases/6.10/ first link.

I booted to it, but I'm not sure where or how to install mdadm. I'm not very familiar with Linux.

Ty!


Grab a Linux live CD, install mdadm raid tool, cross your fingers, and try to rebuild.
Addendum

Alright, I'm gonna try the alternate install CD here instead, looks like that one has what I need, correct?
http://old-releases.ubuntu.com/releases/6.10/

I'm assuming that trying to rebuild a RAID 0 will probably not be fruitful. Is it alright that the RAID zero has a Windows 7 os which I'm trying to recover?

Thx again!

Addendum

The alternate CD is not bootable, so I'm stuck again :smile:
 

mqudsi

Mostly Harmless
Staff member
#4
Rebuilding a RAID isn't for the faint hearted. It doesn't matter that it's Windows on the drive, but it's almost all command-line (there's little to no GUI for this stuff, this is hard-core server admin tools we're talking about).

There are paid, commercial utilities for Windows in the form of other bootable CDs that have slightly easier to use, somewhat point and click (but still lots of numbers and info involved), but I have no experience with those. I'm afraid I can't hold your hand through this, you're going to need to make heavy use of Google. I'm just letting you know that your data *can* be retrieved, I've done so several times with the aforementioned Linux utilities if you're willing to brave it.
 
#5
I'm still at it.... I got the os to show in the list of the windows 7 repair by changing the active partition to #2 on Drive 0 (There are 2 physical drives configured in a RAID 0, the first physical drive seems to have 3 partitions, 2 small ones, and a big one.) Wierdly, it shows the windows 7 install being on the e: drive though, not the c:

So, next...

I burned the Win7 64bit pro .iso from digital river (http://www.mydigitallife.info/official-windows-7-sp1-iso-from-digital-river/) and attempted a repair from the Win 7 installation disk. The repair fails with the same boot sector problem I've encountered before.

I went to the command prompt from the repair GUI after the failure and ran:
chkdsk / r c: which appears to run fine
&
bootrec /fixboot (as well as the other switches) which don't seem to fix anything.


After doing that, I try to boot normally and the system blue screens immediately after the windows logo starts with the error:
unmountable_boot_volume (only able to see that by using the "don't reboot on error" option at F8)

As I mentioned, at the repair menu, it does find a windows 7 installation, but it's on drive e: and not c: ? I'm perplexed by that...
Perhaps I'll try to boot into "mini Windows XP" from Hiren's bootCD and run the disk manager to have a look at what it can see?

Otherwise, any other ideas, I feel close - but for all I know the RAID is just totally hosed. I've fiddled with the active partitions and I've fiddled with fixing mbr's on the partitions, so I could be all messed up now. Drive 0 seems to have 3 partitions, 2 small ones, and then a large one. I'm not sure which one should be the active and which one needs the mbr for windows 7.

I really hope the disk can be repaired and that I can boot into windows 7 and all will be hunky dory, soon :??

Ty much!

Rebuilding a RAID isn't for the faint hearted. It doesn't matter that it's Windows on the drive, but it's almost all command-line (there's little to no GUI for this stuff, this is hard-core server admin tools we're talking about).

There are paid, commercial utilities for Windows in the form of other bootable CDs that have slightly easier to use, somewhat point and click (but still lots of numbers and info involved), but I have no experience with those. I'm afraid I can't hold your hand through this, you're going to need to make heavy use of Google. I'm just letting you know that your data *can* be retrieved, I've done so several times with the aforementioned Linux utilities if you're willing to brave it.
 

Terry60

Knows where his towel is.
Staff member
#6
Don't worry about disk letters.
They are not a physical attribute of the partition in the way that the Volume Label is. It is written in the MBR partition table and is therefore constant and visible to any interrogating software of whatever description.
The disk letter is an ephemeral Windows artefact, just an entry in the registry of the running system, and the fact that your OS calls itself "C" in its own registry has no bearing or influence on any other software looking at it.
The Vista/7 repair disk is an OS in its own right and will label partitions sequentially in the order it detects them without reference to how they think of themselves.
Linux, looking at a Windows partition will tell you its Volume Label (if you gave it one- always a good idea), but not mention a letter at all. It doesn't use them.