What does dd write stuff on a input/output error?












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I have a drive that's on the verge of failing (C5 a C6 are triggered) so I decided to make another backup while I still can, and for that I'm using dd to another drive (exact same model).

However, and kind of as expected, I have some input/output errors, and I'd like to know what dd does when it encounters this error. Does it just skip the sector and writes nothing? Or does it replaces the data that was previously on the target drive with 0s?

Also, since I'm using 64K blocks, can I run dd at the location where the copy failed with a smaller block size to try to get a little bit more data out of it?









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    I have a drive that's on the verge of failing (C5 a C6 are triggered) so I decided to make another backup while I still can, and for that I'm using dd to another drive (exact same model).

    However, and kind of as expected, I have some input/output errors, and I'd like to know what dd does when it encounters this error. Does it just skip the sector and writes nothing? Or does it replaces the data that was previously on the target drive with 0s?

    Also, since I'm using 64K blocks, can I run dd at the location where the copy failed with a smaller block size to try to get a little bit more data out of it?









    share







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      I have a drive that's on the verge of failing (C5 a C6 are triggered) so I decided to make another backup while I still can, and for that I'm using dd to another drive (exact same model).

      However, and kind of as expected, I have some input/output errors, and I'd like to know what dd does when it encounters this error. Does it just skip the sector and writes nothing? Or does it replaces the data that was previously on the target drive with 0s?

      Also, since I'm using 64K blocks, can I run dd at the location where the copy failed with a smaller block size to try to get a little bit more data out of it?









      share







      New contributor




      user333483 is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
      Check out our Code of Conduct.












      I have a drive that's on the verge of failing (C5 a C6 are triggered) so I decided to make another backup while I still can, and for that I'm using dd to another drive (exact same model).

      However, and kind of as expected, I have some input/output errors, and I'd like to know what dd does when it encounters this error. Does it just skip the sector and writes nothing? Or does it replaces the data that was previously on the target drive with 0s?

      Also, since I'm using 64K blocks, can I run dd at the location where the copy failed with a smaller block size to try to get a little bit more data out of it?







      hard-disk dd





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