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I have a question if I'm going to be able to restore this partition if I order replacement drives. zpool clear didn't seem to do anything.

  zpool status Partition1                                                                                         
  pool: Partition1                                                                                                                  
 state: UNAVAIL                                                                                                                     
status: One or more devices are faulted in response to IO failures.                                                                 
action: Make sure the affected devices are connected, then run 'zpool clear'.                                                       
  scan: scrub repaired 0 in 10h33m with 0 errors on Sun Jun 29 10:33:28 2014                                                        

        NAME                                            STATE     READ WRITE CKSUM                                                  
        Partition1                                      UNAVAIL      0     0     0                                                  
          raidz1-0                                      UNAVAIL      0     0     0                                                  
            gptid/7880bcd3-9f15-11e2-8042-14dae968612d  ONLINE       0     0     0                                                  
            gptid/79212bbb-9f15-11e2-8042-14dae968612d  ONLINE       0     0     0                                                  
            17842932853166739482                        REMOVED      0     0     0  was /dev/gptid/79cd72d2-9f15-11e2-8042-14dae9686
            5304850985652021287                         REMOVED      0     0     0  was /dev/gptid/7a75bff5-9f15-11e2-8042-14dae9686
            gptid/7b2692b0-9f15-11e2-8042-14dae968612d  ONLINE       0     0     0  

Guessing raidz1-0 means it is z1 raid? I won't be able to send it to a professional, so any input from you guys would be helpful.

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up vote 0 down vote accepted

A RAIDZ1 pool in ZFS can sustain a single disk failure. Two drives failed means that the pool is faulted/failed/unusable.

So no, you're out of luck with this pool and may want to reach out to the FreeNAS support or other ZFS experts to see what's salvageable.

Do you have any backups?

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no backups I never guessed 2 drives would go at once, but did just get both drives back online. It looks like some of the data is still there as some software residing on that partition started working. Looks like all of my 3D/CAM work is still good. Hopefully they keep chugging along until I can get a replacement as from what I understand you can't upgrade from z1 to z2 without destroying the pool first. – atrueresistance Jul 15 '14 at 2:05
What type of hardware is this? Have you ruled out problems with the controller or the disk backplane? – ewwhite Jul 15 '14 at 2:06
Mini ITX motherboard using onboard sata slots in a 3u rackmount case. Home built freenas. Never had an issue before with the hardware. A reboot is what fixed it. – atrueresistance Jul 15 '14 at 2:26

As ewwhite said, raidz1 is like raid5, only one disk can fail without loss. But if you can get those other disks back in there and get them to work, you have a chance. That's likely not going to happen, but if you care about the data (in which case you should have had backups), you can try it. Just stick an apparently dead disk in the fridge to cool it, then use dd to image the bad disk to another good disk if it runs at all, until it fails, then repeat, etc.. Then you might be able to get the pool online with the new copy on the good disk, and you might lose a few files rather than a whole pool.

And if the bad still spin up and you can read them, but they just had too many errors for ZFS to keep them, you don't even need the fridge. Just clone them, or even just zero the bad sectors, and do the same.

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Thank you for the little fridge trick. I did get lucky and got both drives back online. Thinking it is the cable connection either way I'm not going to take any chances. Got the very important stuff off, and am .7z the rest to rebuild to z1. – atrueresistance Jul 18 '14 at 0:02

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