Rapid Storage Technology
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Finding IRST RAID 5 properties for recovery

UAlon
Beginner
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Hi,

I'm attempting to recover a 5-disk RAID 5 volume which marked 2 drives as failed (although they're intact) and is completely inaccessible by IRST.

Various recovery apps need some RAID properties in order to recover the data, and I wonder if I can get the following information:

  1. Block size: I know it's 128 KB
  2. Block order: left/right synchronous etc.?
  3. Disk order: is there a way to retrieve it? Maybe from the raw data on the disks? Otherwise I have 32 combinations to test...
  4. Parity delay?
  5. Anything else I'm still missing at this point?

Thanks,

Ury

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David_V_Intel
Employee
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Hello UAlon, Thank you for posting on the Intel ® communities. I would like to gather some information in order to assist you in the best way. Please provide me with a system report, this report can be generated by following the steps in the link below: https://www.intel.com/content/www/us/en/support/articles/000006351/technologies.html Also, keep in mind that the fault tolerance of a RAID 5 is only 1 disk, if 2 disks have failed then there should not be a way to rebuild or recover the RAID 5. Regards, David V Intel Customer Support Technician Under Contract to Intel Corporation
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UAlon
Beginner
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Thanks David.

The system report is attached.

As I mentioned, I'm not hoping to restore the RAID using IRST. I'm doing it with 3rd party apps. All the disks are fine. Now I'm pretty sure they were removed from the RAID array because of a BIOS update. Assuming that's the case, f there's a way to recreate the RAID using IRST without losing data, it would be lovely. If not, I just need the array properties for 3rd party reconstruction.

Regards,

Ury

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David_V_Intel
Employee
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Hello UAlon, Thank you for your response. The information you require cannot be retrieved using Intel ® Rapid Storage Technology. What you can try to do is to remove the good drive and insert it in a different computer, which sometimes can actually show data stored. Nevertheless, I cannot guarantee that you will be able to access the data. Also, according to the Intel ® Rapid Storage Technology system report, there is no RAID configured so I would recommend to check the good drive and try to access it via windows* explorer to see if the data is accessible and if so, back up any important data. Regards, David V Intel Customer Support Technician Under Contract to Intel Corporation
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UAlon
Beginner
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Thanks David,

First, according to the report, there's no RAID configured because I intentionally disabled IRST in order to be able to at least try to salvage some of the lost data using 3rd party software .

 

Second, before concluding that the information cannot be retrieved and I should give up my data (it will take me a couple of months to restore it from "backups"), let's look at the information I'm looking for item by item:

  1. Block order: not "knowing" if IRST uses left or right synchronous block order is like telling me that Intel doesn't know if its CPU are little or big endian... It's a major design decision, hard-coded into the implementation. It's not configurable, it doesn't change from one installation to another... how can it be unavailable??
  2. Parity delay: same as (1) above
  3. Disk order: if this information does not reside anywhere, how does IRST load the array every time the machine is rebooted? I'm not expecting it to be in a plain text file, but maybe it's in Windows' registry or IRST's proprietary configuration files? I also have access to all disks' raw data, so if this disk ID is on a fixed location on the disks, I can get it from there. I honestly don't understand how can the array disk order could not be available anywhere.

Regards,

Ury

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David_V_Intel
Employee
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Hello UAlon, Please provide me with the following information: Motherboard model: BIOS version: Intel ® Rapid Storage Technology Option ROM version(you can access this normally by pressing Ctrl+I during POST): Intel ® Rapid Storage Technology OS version(the normal GUI version, within the O.S): Windows version: SATA Mode (AHCI/RAID): RAID configuration: Also, please provide me with the System Support Utility report, this report can be generated from our tool, you can refer to the link below so you can download it:  https://downloadcenter.intel.com/download/25293/Intel-System-Support-Utility-for-Windows- Make sure to attach the created report to this thread. Regards, David V Intel Customer Support Technician Under Contract to Intel Corporation
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David_V_Intel
Employee
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Hello UAlon, Were you able to check my post? Please provide me with the information requested so this way I can assist you further. Regards, David V Intel Customer Support Technician Under Contract to Intel Corporation
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David_V_Intel
Employee
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Hello UAlon, Please contact us if you have any additional questions. Regards, David V Intel Customer Support Technician Under Contract to Intel Corporation
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UAlon
Beginner
868 Views

Hi David,

I'm making progress with the recovery.

As soon as I have results (within a couple of days), I will provide full feedback.

Thanks,

Ury

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