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Old 10th November 2011
sharris sharris is offline
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Default dd'in:: How to skip the first 32256 bytes?

I am planing on trying a few things that may cause me to loss data. This is not a problem. The problem would be having to reinstall a few OS than trying to do it all over again until I get it right. This could take days.

I once thought the MBR was only 512 bytes, but that's not all. Something is using the first 32256 bytes on all or most HDD's. It could be the dealing of Windows on the first primary of my dual-boot machines. Anyway, this prove that something more is between the MBR and the very first useable partition. But this is not the issue either. I been happy to know how to deal with this all year, finally.

Make a copy of full MBR:
Code:
dd if=/dev/sda of=/mnt/MBR-WinOnP1 bs=32256 count=1
Restore full MBR
Code:
dd if=/mnt/MBR-WinOnP1 of=/dev/sda bs=32256 count=1
and it never fail!


OK, here's my question:

Now I want to skip this entire area and try something difference.

Would the code below skip the first 32256 bytes and start zeroing out the HDD from position 32257 to the very end of the disk. If not, could someone show me the dd sequence of how to do this, including another one that allow me to skip, than dd up to a certain point than stop?

Code:
dd if=/dev/zero of=/dev/ad4 bs=32256 skip=1 conv=notrunc,noerror
Thanks in advance
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