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How unlikely is it that a mirrored raid of 2 ssd drives fail together. (Both sector 0) unreadable.

Me is told that ssd generally never breaks. So that both break at same time seems unique.

What are chances of recovery when I get the drives shipped to me since even rescue systems won't recognize (centos plesk server)

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It's quite unlikely but at the same time, not impossible. As always, a RAID is no substitute for a backup. If you don't have a backup, something like this is guaranteed to happen!

Recovery: It's impossible to say since it's not clear what the issue is in the first place. I would say that if rescue systems didn't even see the drives, your chances to do it yourself are near zero. Having two drives fail at the same time is a strong indication for external issue like electric or thermal damage. When in doubt, send it to professionals.

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  • after few reboots, it showed a few times.. And there where backups but they all seem corrupt for some reason. May 14, 2016 at 7:31
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    Backups where restoration is not regularly and comprehensively tested aren't worth the tape they're written on.
    – MadHatter
    May 14, 2016 at 8:35
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Depends on the batch of drives that they came from. The (poor) theory is that if hard disk 1 has probability of failure 1/1000 and so does disk 2, then the probability of both failing is 1/1,000,000. That assumes failures are statistically independent. This is a major mistake as they are not. You can’t just multiply probabilities like that unless the failures are uncorrelated. Wrongly assuming independence is a common error in applying probability. As far as recovery goes, SSDs are not hard drives. If you are lucky, and the system is looked at by a professional recovery service , the issue was with the controller and not the SSD. If the NAND itself went bad, there is no recovery option.

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