how to retrieve data from broken RAID5
 

Hi,
I would like to know is there a way to retrieve data from a broken RAID 5 HDDs? My situation is described as below.

Hardware Configuration:
- two Opteron processor
- 4GB RAM
- one RAID controller: LSI MegaRAID 150-6
- HDD: 3x 250GB (in RAID 5 mode)

Situation:
- the server is installed with SUSE10.0 and the system hang.
- the server then force to hard reset and found the OS corrupted very badly.
- the team decided to reinstall the OS so to power up the system asap, by replacing a new set of HDDs.
- the 'old' set of HDDs then move to the other server (with same hardware config) to perform data recovery, but the HDDs accidently re-initialized in the RAID controller BIOS.
- after that, the whole set of HDD cannot boot any more and even the SUSE rescue disk can't find the entire array.

Therefore, does anyone know the way to retrieve the data? Or is the data is completed lost?

thanks a million for any advise.

There are commercial companies that may be able to recover the data.. very very expensive. I think my last quote for a 6 Drive 1 TB RAID 5 array recovery started at $20,000.00


You could also try contacting LSI to see if they can tell you how to get the controller to re-read/recreate the proper information from the drives to get the array back.. The system should have allowed you to import the RAID configuration instead of re-initializing the array.


Quite honestly at this point I would suggest doing a restore of the data from your most recent backup.

thanks, farslayer.
i think there is no choice for this. will approach LSI for the final hope. thanks again for the advice..

2 Q's & a comment:

Is this a true hardware RAID (as opposed to "fake RAID") controller? -- Nothing I found on the 'Net, not even on their own site, definitively answers this Q.

It would be be helpful if you supplied one or more links to pertinent info. when asking Q's about hardware.

Have you examined the disks w/ dd or other low level tool? Perhaps w/ a live CD.

Hi,
Thanks for the advise.
Here is the link for the LSI RAID card ( http://www.lsi.com/storage_home/prod...506/index.html ).
I don't remember the site but it did mentioned that this RAID controller is a hardware RAID.
I did not check the method you mentioned, but will give a try tomorrow :)
Anyway, thanks for the advice :)

When the drives were placed in the recovery server, where they put back in the correct order? I don't have a lot of experience using SATA raid cards, but with SCSI if the drives are out of order the controller will not see the original volume. The disks should still have the data as long as they have not been repartitioned or formatted.

From http://en.wikipedia.org/wiki/RAID#Hardware_RAID

My impression, possibly erroneous, is that the need for drivers is a tell-tale sign of Fake Raid.

How much did this card cost & where was it purchased?

Dis you have any luck contacting LSI?

If I understand you properly, you have the data you want on disks you have moved to a new system, and want to make them usable.
Ordinarily, I'd say get the LSI config tool at boot (ctl-S usually) and tell it to recover 'foreign-config', which will find the RAID tags writted to the disks and re-assemble the array...though they may need to be in order, as mentioned above. If it has already been re-initialized, this option will likely no longer exist.

From the sound of it, the poweroff may have caused problems at the fs level, so recovering the RAID will only get you back to where you were on the other server. Then you will have to use an appropriate tool to try to put the fs back in order. Not sure which fs you are using
I have heard of gradual corruption problems with older LSI RAID cards, but not all at once.

DreamerX,
Did you find a solution? . . .
What is it?

Hi,
I find there is no solution for this. Because when I perform fdisk and it printed there is no partition for the array. So, I think the MBR should be overwritten by the RAID card during initialization.
Anyway, my teammate has give up on the recovery and keep going on other works.

thanks and appreciated your support.....