RAID5 array rebuild help and R-studio help

Discussion in 'SSDs & Data Storage' started by runnin17, May 20, 2014.

  1. runnin17

    runnin17 [H]ard|Gawd

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    Okay, so my RAID5 array went out last night. Woke up this morning to this and went to check everything. No power failures, no SMART errors and drives in the array seem to be fine.

    No new data written to the disks at all. This is all mostly non-important data, but it is about 7TB of data so I would like to recover it if I can :)

    All the important data has been backed up so there is no concern there.

    Specs on the array.
    4 3TB seagate drives (no hot-spare) in RAID5
    The event log showed that the 2nd and 3rd drive in the array were failed. That is what made me suspect some random error and not a true drive failure.

    In the process of rebuilding the array now to see if everything is okay. If not, then it is time to play around with R-studio. I have not done any of the rescue commands and the disks are all in the correct order. I have all the correct information about drive order and array parameters.

    I guess the questions are, what is the best way to go about doing everything correctly with R-studio? I have three extra 3TB disks that I can use, since there are 4 drives in this array do I need to pickup another 3TB disk to make a perfect image for R-studio?

    Thanks in advance for any help.

    UPDATE: Rebuild stalled at around 68%. Device log shows multiple reading errors on one of the drives in the array. I guess it is time for R-Studio. Need some tips from here on out as I am completely new to R-Studio.
     
    Last edited: May 20, 2014
  2. mwroobel

    mwroobel [H]ardness Supreme

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    Before you do ANYTHING make a complete image of all the original drives and ONLY work on the copies. How was the array originally created. HBA or motherboard controller (and which one), what filesystem, any logs you may have, etc?
     
  3. drescherjm

    drescherjm [H]ardForum Junkie

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    Fully agreed. That way you minimize the risk of losing everything. And if you have a raid (especially raid5) you should have a backup anyways. After the raid array is fixed use the second set for a backup/
     
  4. runnin17

    runnin17 [H]ard|Gawd

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    Array created with Areca 1882 card. NTFS filesystem. In the process of making images of the original drives. They are large drives, so it will take awhile.

    All the important data has been backed up anyway. I am not too worried about what I might lose since all but maybe 500GB has been backed up. This is just a chance for me to become intimately familiar with R-studio I guess, lol.
     
  5. mwroobel

    mwroobel [H]ardness Supreme

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    Please post the complete log from the Areca.
     
  6. runnin17

    runnin17 [H]ard|Gawd

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    Multiple read errors on disk #2 and #3 in the array. Very odd that both disks would have read errors at the same time. Disk #2 fails consistently and does not want to stay within the array. Even unable to make a full image of the disks due R-studio running into data errors while trying a byte for byte copy of the disks. Oh well, glad I keep fairly regular back ups. I know a little more about R-studio now.

    I have been wanting an excuse to maybe move over to zRAID, this might just be it :)
     
  7. drescherjm

    drescherjm [H]ardForum Junkie

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    Use ddrescue to make a bit for bit copy of the bad disks to new disks then rstudio to recover the array using the new disks instead of the old.
     
  8. runnin17

    runnin17 [H]ard|Gawd

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    I thought about that, but I think my time is better spent on playing around with zRAID and getting the backed up information in another backup place :)

    I might spring for a few more 3TB drives, likely some more WD Reds or some of the 3TB toshiba's that are right at $105 a piece. I have another 24 bay server box I need to play around with that has been gathering dust.
     
  9. Aesma

    Aesma [H]ard|Gawd

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    Consider RAIDZ2 or RAIDZ3 with 2TB drives and bigger.
     
  10. runnin17

    runnin17 [H]ard|Gawd

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    I have done a bit of reading. Most likely going to go with RAIDZ3.

    I am actually new to linux and the ZFS file structure, so I am still reading on what is the best option for a simple home server NAS box. My main concern is just to be able to have access to the data on the server from my other Windows PCs in the house.