I remembered reading one question how would you back up the MBR of a disk.
Two of the choices are
dd if=/dev/sda of=/dev/sdb bs=512 count=1
dd if=/dev/sda of=/dev/sdb bs=440 count=1
and the correct answer is
dd if=/dev/sda of=/dev/sdb bs=440 count=1
I am confused. Is the MBR size 440B or 512B ?
Best Answer
The MBR IS 512 bytes. So the first example is how you would back it up. The partition table is at the end, in the area after 440 bytes in - so, if you wanted to back it up WITHOUT the partition table, then you could use the second example (why you'd want that, I don't know).