RAID5 - 8 disks

Discussions on using the professional data recovery program R-STUDIO for RAID re-construction, NAS recovery, and recovery of various disk and volume managers: Windows storage spaces, Apple volumes, and Linux Logical Volume Manager.
Prohias
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Joined: Wed Jan 28, 2009 12:53 pm

RAID5 - 8 disks

Post by Prohias » Wed Jan 28, 2009 1:36 pm

One Promise EX8350 contoller stopped working. The three year warranty gave me a new EX8650 controller.
What they forgot to tell me was that it is not compatible with the old controller :evil:

It seems to me that R-Studio can help me but before I start this quite big operation I'd like to be sure.

All 8 disks now connected to new controller and have status OK. I have not done anything with the new controller except looking for the non excisting "Make these disks one RAID again"-option.

If I connect the disks to standard SATA-controller one by one and create image files.
Will I then be able to use these 8 images in a virtual RAID5 and try to recover from there ?

The disks are marked 1-8 according to the ports on the card. Will R-Studio ask for this or should I just add them in sequence ?

I can't imagine I used anything but default settings when I made the RAID. Do you know the typical settings for Promise RAID5 ? (8350-controller). I'm quite sure it's 64kB block size but have no idea about blocks order.

Prohias

Alt
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Re: RAID5 - 8 disks

Post by Alt » Wed Jan 28, 2009 5:29 pm

1. Yes, you can use the images of these disks to create your virtual RAID 5.
2. You have to arrange the disks in the Parents tab manually, 1 at the top, 8 at the bottom.
3. I think the best way to learn the default settings is to ask Promise technical support. They should know. As obviously there was no file system crash on the RAID, once the settings are correct, R-Studio should find a valid partition with a file system. I recommend you to check that additionally by previewing the files on the RAID. Just double-click the selected file. You may find the list of supported file types in R-Studio Help - Data Recovery Using R-Studio - Basic File Recovery - Previewing Files. The file size should be large than Block size x (Number of all disks - Number of parity disks).
Good luck in data recovery.
PS. Some RAID controllers, when find new disks, automatically initialize a new RAID, effectively deleting old file system information therefore making data recovery much harder.

Prohias
Posts: 4
Joined: Wed Jan 28, 2009 12:53 pm

Re: RAID5 - 8 disks

Post by Prohias » Mon Feb 02, 2009 2:12 pm

I'm waiting for a reply from Promise support. Unfortunatly 24/7 support only meens that you can ASK questions 24/7.

Best so far : Left AsynchronousCapt / 64kb / no offset :
The complete folder/file structure is visible. Not much luck with previews, BUT I managed to play a mp3-file.

Thought that could give some clues because it's like the song is chopped up and the pieces played back in wrong order....

I've also noticed that the image of disk 1 and 3 has a "Partition1" NTFS with start 31,5kB (Capture02)
And that at one point of the scan ALOT of messages are generated. (Capture01)

Any further tips would be great.
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Prohias
Posts: 4
Joined: Wed Jan 28, 2009 12:53 pm

Re: RAID5 - 8 disks

Post by Prohias » Mon Feb 02, 2009 6:05 pm

Never mind my previous post - I figured it out.

From my experience :
- Try to preview mp3 files if you have any. They seemed likely to play even if the settings weren't correct yet.
- If it sounds like the song is chopped up and the pieces plays back in wrong order, try changing the block size.
- Promise EX 8350 uses Left Asynchronous Block order.
- Promise support is quite useless.
- R-Studio is fantastic

Now let me find my credit card so I can get a license for this amazing software and get back to work. :D

esseeayen
Posts: 2
Joined: Sat Jul 03, 2010 12:39 am

Re: RAID5 - 8 disks

Post by esseeayen » Sun Jul 04, 2010 8:03 pm

Heya i hope you still read this forum, i know it was a while ago but now i have gotten into some strife on a 7 disk raid 5 array with my promise EX16350. I am going to start doing the raid recovery soon (fingers crossed it works) but i am wondering how did your recovery go? What settings did you use? I pretty much used the default settings on the promise array so i am quite sure they would be the same as yours!

Thanks in advance!

Sean

Prohias
Posts: 4
Joined: Wed Jan 28, 2009 12:53 pm

Re: RAID5 - 8 disks

Post by Prohias » Mon Jul 05, 2010 4:15 am

Hello Sean

My recovery was 100% successful.
I used Left Asynchronous Block order with 128kb blocksize and no offset. Note that 64kb is the default ! (On EX8350)

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BTW. My EX8650 reported two 'dead disk' earlier this year and would not start up.
Disk is marked as dead if it can no longer reassign write-errors I think. But how about giving a warning BEFORE it's 'dead'.....
(Probably possible with WepPAM software but it's not easy to configure..)

Anyway, all disk was still working so R-Studio once again saved the day with a 100% recovery.
This controller used Right Asynchronous Block order so I had to do some trial and error again.
I can also confirm that Promise support still sucks. They either answer you with a stupid question or tell you to restore from your backup.

esseeayen
Posts: 2
Joined: Sat Jul 03, 2010 12:39 am

Re: RAID5 - 8 disks

Post by esseeayen » Mon Jul 05, 2010 6:49 am

Heh, i know what you mean about the promise web pam, its so counter-intuative!

My raid array went critical and started to rebuild itself with all the same drives still in place and i powered off and removed the drives, put some different drives in to put into a new array but when i plugged in my new array it said that it was offline!!!! Now why it didn't tell me anywhere that my array went critical or started rebuilding i will never know!

i am just hoping that i may be able to recover my data! here's fingers crossed! :(

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