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Re: DD bs=4M option on USB mem-stick creates false format




On Mon, Mar 27, 2017 at 11:45:00AM +0000, kAt wrote:
> Yes, all this was done, the image on the stick is fine and functional!
> I did not say there was a problem with it, but the rest of the unused
> space ob the disk/mem-stick

When you write a disk-image onto a "disk" (in this case, a USB mass
storage device), you are overwriting all of the metadata at the start
of the "disk", including the partition table.  If the disk-image came
from a 4 GB disk, and you write it onto an 8 GB disk, then the 8 GB
disk will *believe* that it is a 4 GB disk, because it has the metadata
from a 4 GB disk.

As others have said, this has absolutely nothing to do with the bs=
option in dd.  All that does is make the dd command run a tiny bit
faster or slower.