I have some locally stored media i was copying between drives and one mkv file gave this error error reading 'video1.mkv': Input/output error and only copied 176/256 MiB; the copied file plays the video only up to a certain point before abruptly closing; I can play the original file fine albeit there is a noticeable hitch at that point but the video plays normally till the end I have tried zipping the file but it fails to zip it I tried copying it using ffmpeg but it also gave the same error I can copy the file in the same directory but trying to copy the copy also gives the same error I tried copying to a variety of different storage drives and it still gave me this error any ideas?

  • Yote.zip
    link
    fedilink
    English
    51 year ago

    It goes without saying but the number of errors you should get on a scrub is ideally 0. Bitrot happens from time to time which is why you should keep some data redundancy/backups so you can repair it when it’s detected, but that number seems higher than normal. Your disk may be going bad if you’re getting that many read errors; I’m not sure. I believe you’re already backing up data off this drive but yeah I would get everything important off the drive ASAP, then run a SMART short test and a SMART long test to see if that reports that anything is wrong. The disk may be fine but better to be safe than sorry.

    Back to the video file, I’m assuming it was not one of the ones that BTRFS fixed automatically? The only real options for data recovery are to rescue the file minus the bad blocks with e.g. ddrescue (which I don’t personally have familiarity with) or something similar, or to encode through the errors with ffmpeg if it will let you.

    • @[email protected]OP
      link
      fedilink
      21 year ago

      A SMART Test showed 6 bad sectors but overall disk assessment was ok(I dont think there is any connection between the file and the HDD), yes that file has not been fixed, the disk in question used to be my main bootdrive a few days ago, I shrunk the partition and created a new EXt4 and i am slowly copying files that are worth keeping, i removed the ODD from my laptop and installed a caddy, intend to use it as a second drive(The file in question has no sentimental value)

      • Yote.zip
        link
        fedilink
        English
        41 year ago

        Okay cool. I would be wary of that drive just in case, and I would definitely schedule weekly SMART short tests and monthly BTRFS scrubs on it if you go with BTRFS in the future. EXT4/XFS/etc do not have a concept of data checksums, which means they can’t scrub and check for bitrot - this might be problematic if you find that your disk starts causing bitrot because you won’t know where it’s happening.

        I follow Backblaze’s rules on detecting impending drive failure:

        • SMART 5: Reallocated_Sector_Count.
        • SMART 187: Reported_Uncorrectable_Errors.
        • SMART 188: Command_Timeout.
        • SMART 197: Current_Pending_Sector_Count.
        • SMART 198: Offline_Uncorrectable.

        If any of these SMART metrics are higher than 0 I’d expect failure soon and take precautions.

        • @[email protected]OP
          link
          fedilink
          11 year ago

          Thank you Id 197 and 198 reported 5 & 6 respectively(bad sectors decreased from 6 to 5), Is it possible to copy a file non sequentially; say back to front so i can just join those 2 parts together?

          • Yote.zip
            link
            fedilink
            English
            21 year ago

            Try this answer. I guarantee there is a way to read the file front to back while skipping errors, but I run so much data redundancy that I don’t have any experience with it.