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Two drives failing, I can only save one right now, how should I proceed?

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Michael
2015-07-01
2015-07-13
  • Michael

    Michael - 2015-07-01

    What would be the best way of using Snapraid to recover both these drives, but not at the same time?

    For instance I can replace Drive One immediately, but Drive Two I won't be able to recover for a week or more, until I can buy a big enough replacement drive.

    More than likely I'm going to pull the Drive Two completely out of the PC so it's not being used at all, but I don't want to lose the backed up Snapraid sync of that drive after I recover Drive One and resync.

    Thank you.

     
  • Leifi Plomeros

    Leifi Plomeros - 2015-07-01

    If the disks are still working, then the best strategy is:

    1. Decide which disk you think is most likely to fail first or just choose one of them.
    2. Manually copy all data from the selected disk to a new disk
    3. Replace the disk old disk with the new disk.
    4. Run sync to make Snapraid aware that you have replaced the disk. It will only take a few seconds to check that all files are present and update the content-file with information about the new disk.
    5. Wait until you can afford a new disk and repeat step 1-4.
     

    Last edit: Leifi Plomeros 2015-07-01
  • Michael

    Michael - 2015-07-05

    One of the two drives went down hard, I can do what you suggested for one of them, but what's gonna happen when I try to sync with the second drive missing?

     
  • Leifi Plomeros

    Leifi Plomeros - 2015-07-05

    Syncing with a missing drive is completely out of the question. Snapraid won't let you and if it did then all data from the missing disk would be permanentely lost.

    The most straightforward solution would now be to:

    1. Replace the completely broken disk
    2. Run Snapraid fix to restore the broken disk
    3. Run Snapraid sync
    4. Wait until you can afford a new disk
    5. Replace the not yet failed disk by manually copying files.

    However if the other disk dies during the fix, then you are in real trouble.

    The alternative method would be to manually copy/replace the soon to fail disk first and fix the lost disk last.

    But since you don't have a second replacement disk to use, it is probably better to recover the lost one first. This way you minimize the risk that while you are waiting, a third disk suddenly breaks down, leaving you with two lost disks and no recovery scenario possible.

     
  • Michael

    Michael - 2015-07-05

    Syncing with a missing drive is completely out of the question. Snapraid won't let you and if it did then all data from the missing disk would be permanently lost.

    Yeah, I was pretty sure that's what would happen, which is why I wanted to get some input first.

    Thanks for the input and all your suggestions.

    Multiple drive failure "plans of action" should be updated in the manual.

     

    Last edit: Michael 2015-07-05
  • Michael

    Michael - 2015-07-12

    Out of curiosity, does anyone know if you replace a failing disk with a disk that has some data already on it, will Snapraid erase that data in the fixing process?

    I'd assume it wouldn't erase any data, but I'm still curious.

    Also, my disk is restoring at about 8 megabytes a second, at this rate it's going to take ~2 weeks (350 hours according to SR) to recover the entire drive, does this sound normal?

    Thanks!

     

    Last edit: Michael 2015-07-12
  • ZeroCooL

    ZeroCooL - 2015-07-12

    SnapRAID works with mount points to you can restore to a folder on a drive and the other files/folders would stay. 8mb/s sounds fishy to me i was able to restore a single 1GB file almost instantly granted that's not a full drive tho. But i have heard other doing its 8-12 hours not 2 weeks.

    --James

     

    Last edit: ZeroCooL 2015-07-12
  • Michael

    Michael - 2015-07-13

    Thank you, I thought the files would be fine I just wanted to be 100% sure.

    A restart fixed the speed issue, now i'm getting like ~300+ MB a second. That's more like it. :)

     

    Last edit: Michael 2015-07-13
  • ZeroCooL

    ZeroCooL - 2015-07-13

    That's good to here :). GL with the recovery

     

    Last edit: ZeroCooL 2015-07-13

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