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okamon

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how to retrieve data from failed raid

I was always able to retrieve data from a single hard drive be using a usb adapter and plug into a working pc. Just wondering how can I do it with Raid if that says 2 hard drive failed in raid 5.
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Em Man
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Nope.  RAID 5 fault tolerance is 1 disk, RAID 6 is 2 disks.

When a disk fails in RAID 5, you must replace it ASAP or risk total data loss if another disk dies in the meantime.  While it's possible for 2 disks in the RAID to fail within a short time period, it doesn't really happen that often.

Unfortunately your data is lost.  Remember, RAID is not a backup.
Depending on the condition of the drives,

If the drives are dead as in "not spinning up or not detected by PC", you need a data recovery service which will do the repair on the drives and then recover the RAID.

In all other cases, you should image the disks and then try software such as RAID Reconstructor or our ReclaiMe RAID Recovery against the disk images.

If one of the drives developed some massive bad sectors, you may leave it out, because RAID 5 compensates for a loss of one drive.

Make sure you have plenty of free space available because you'd need 2 to 3 times the usable capacity of the RAID to work with. A RAID recovery software produces a so-called "destriped" image of the array contents, which you can then feed to a regular data recovery software if needed, or write directly to a disk or LUN to see if it is readily accessible.
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If two drives in a RAID5 dropped out due to hardware failures, no software is going to be able to recover it - you need a data recovery company.  There's a big difference between reading data from a drive and being able to boot from it - recovering from a drive that won't boot is much easier than recovering data from a drive that doesn't work.
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Okamon,

Are you saying that you were able to recover data using Raid Reconstructor?  So you really didn't have 2 failed drives?