hard drive - is it okay to mirror/raid1 different hardisk model in freenas

07
2014-07
  • AzDesign

    In my freenas system, I have several volumes running, one of them is consist of 2 3TB WD RED with different model (I forgot the serial, but they are different). Both are set up in a single mirror volume. I installed transmission plugin for downloading torrents, the location of the jail is also on this volume as well as the download folder location.

    The issues i'm having are that 20% of my downloads always suffered from failed checksum test. "x file piece z which has been downloaded has failed its checksum test". The first thing I did was to check the smart info from each hdd, turned out no errors nor bad sectors was found. One of the hdd also have suffered from failure that it is not detected anymore and volume status changed into "degraded" status. Restarted freenas and the problematic hdd turned on and back to normal, ran another smart test and still no problems at all on both hdd.

    While only running on a single hdd before I restarted, I have not received any checksum errors at all for entire day, but smart test shown no issues on the problematic drive.

    So here are list of possible cause based on my knowledge (listed based on its chance of possibility) :

    1. Mirroring problem between 2 different hdd models (with identical
      size)
    2. Unreliable smart test
    3. Transmission's problem (I have make sure to get its latest version)
    4. Network problem (DNS, ISP, modem, router, etc)

    I'm using freenas 9.1.2 and access my files using cifs share.

    Can anyone elaborate how likely each possible causes occur ? And what should I do about it ? Thanks

    • Answers
    Know someone who can answer? Share a link to this question via email, Google+, Twitter, or Facebook.

    Related Question

    recovery - Recover data from NTFS disk after RAID1 mirror operation
  • Mathias

    I have two identical disks attached to my Asus P5Q Motherboard which are not operating in RAID1 mode. Disk1 (640 GB, almost full) is/was 2 partitions (system, data - both NTFS) and disk2 (640 GB, 80 GB occupied) 1 partition (NTFS) for data only. The problem with the motherboard is, that the default settings are to operate the disks in RAID1 mode. Yesterday somehow the BIOS settings were reset to default (I suspect the battery is empty) and the disks were configured as RAID1. Unfortunately, I realised it only half an hour later (switched PC on and went away) and the controller had that time to mirror disk2 onto the other disk. I tried some recovery programs such as testdisk, photorec and pc inspector file recovery but could only find partitions/data from disk2. Any chance to still access the data from disk1?

    Regards, Mathias


    • Related Answers
  • KCotreau

    The professional version of File Scavenger ($185) can salvage data off even broken RAID drives. That said, because drive 1 was almost full, and 80 GB was written to it, you will almost certainly have lost some data to files being overwritten. However, if there was a lot of one-of-a-kind data, this tool will recover a lot for you. I recovered almost everything off a broken RAID 5 once, including an Exchange (Microsoft e-mail) database.

    http://www.quetek.com/prod02.htm

    In the meantime, do not use the computer, or either disk, as you risk losing more data. You would want to run File Scavenger, or any other data recovery program, from another computer, with the disks you are trying to recover installed as secondary disks.