Rebuilding a RAID Array

[ROb]

i am trying to build a broken RAID having following parameters.

No of Drives - 03 ( 300 Gb each )
Original Configuration - RAID 5
Controller - LSI Serveraid m1015
Strip Size - 128 sectors
Rotation - Known
Parity - Unkown

PROBLEM :
When i received SERVER the there was no VIRTUAL Volume it was broken
Two out of three drives were showing "Configured and good" and one drive had "FOREIGN CONFIGURATION"
Attempt to import "FOREIGN CONFIGURATION" fail. It says import failed.

Trying to Build the RAID outside the system using different application.
On Rebuilding I am able to see the data in proper structure format but everything is garbled.
Few files which are lesser than 64 k ( Stripe size) are working.
What should be probable solution to this ????

[saltwater]

First of all make an image of each drives and load images to Reclaime Free RAID Recovery for inspect you RAID configuration.
Then load the right RAID configuration to you favorite RAID recovery software (R-Studio, UFS Explorer, Reclaime Recovery...)

[Dmitri]

After reading your description I'd suggest that array been working in a degraded mode.
Also chances are there was an improper rebuild.

Should you find yourself stuck at some point, we can connect and look into this RAID remotely.
That will also allow to tell more on what happened.

[ROb]

Yes i have created the images of both the drives and working with the same

I have notices and also was conformed by the client the the HDD at second position was not part of the Array for last 2 years. They were working on this Array in degraded mode. I confirmed the same that the data on this drive is 2 years old. Which means i am left with 2 drives only to work with.
seems Meta data on both these drives is lost as even Linux is unable to read it.

[H13]

I confirmed the same that the data on this drive is 2 years old.

Hi,
what about the new data ?!
between this 2 years ?

why some raids system we can got old data but new data not ?

[MindMergepk]

I confirmed the same that the data on this drive is 2 years old.

Hi,
what about the new data ?!
between this 2 years ?

why some raids system we can got old data but new data not ?

well OP is talking about Meta Data (Raid Configuration) not user data.

since it is RAID5 so data should be available with 1 missing drive how about skipping the fail drive, does it make any difference ?

Dmitri & Dr-Kiev both are highly recommended persons on this forum.

[ROb]

Off course i am trying to Build the RAID with one missing (i.e. Drive No : 2)
With these two drives ideally i should be able to build the Array Outside.
But the data i get in recovery is garbled / junk/ not opening or working . ( folder names and structure is correct )

[H13]

Off course i am trying to Build the RAID with one missing (i.e. Drive No : 2)
With these two drives ideally i should be able to build the Array Outside.
But the data i get in recovery is garbled / junk/ not opening or working . ( folder names and structure is correct )

what about if the client .. make check disk on this array ?!

[michael chiklis]

I prefer to recover raid array via ubuntu instead of using R-Studio or UFS because i get better result via madam in linux.
But in some scenario it may be about impossible to recover the array with linux so in that case i use UFS to recover data (data recovery would not be great in this way).

[ROb]

Tried that but not been able to build it through that as well

[S.Haran]

I agree with michael chiklis. Recovery the Linux way has many advantages over recovery apps. Here's some ideas...

If only small files are recoverable it may be that you are using the wrong RAID parameters. Let Reclaime scan the drives. Does it find the same RAID parameters you've been using?

Where the RAID volume is relatively small at 600GB you could image it and run a Photorec scan to see what it comes up with.

Ask the client for a file that was known to be on the RAID and hex search for it.

Use the LSI RAID controller to make a RAID5 with new drives. And see what you can learn from it.

I created a brute force RAID recovery process that tries all possible RAID parameters to find the right one. If you would like some help send a PM.

[ROb]

Hello,
I had used new drives and created a new array with default settings of RAID5 in LSI RAID Controller ( Same Server ) This Array i am able to build outside and also the data recovered is perfectly working.
Which gives me the parameters which are matching with the ones used by me to rebuild the failed RAID
.
The Parameters are
1) Strip size = 64 k ( Maximum allowed)
2) Block order = left symmetric standard
3) Rotation = known
4) Offset = zero

I have been trying to use these parameters but still the data recovered is corrupted only. some Files of smaller size than 64 kb (strip size) are working

[einstein9]

Hello,
I had used new drives and created a new array with default settings of RAID5 in LSI RAID Controller ( Same Server ) This Array i am able to build outside and also the data recovered is perfectly working.
Which gives me the parameters which are matching with the ones used by me to rebuild the failed RAID
.
The Parameters are
1) Strip size = 64 k ( Maximum allowed)
2) Block order = left symmetric standard
3) Rotation = known
4) Offset = zero

I have been trying to use these parameters but still the data recovered is corrupted only. some Files of smaller size than 64 kb (strip size) are working

Hi ROb,

i can have a quick look remotely if you want
PM if needed.

good luck