Re: [gentoo-user] low-level formatting a harddrive

[Scott Tiret <stiret@oneredshoe.net>]

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On Wed, 2005-10-19 at 09:28 -0700, maxim wexler wrote:
> 
> I wonder if there isn't a tiny part of the drive that
> comes before the first partition, like those first few
> grooves on a vinyl record ;-)

There is.  You can reset it by using fdisk /mbr (from the Microsoft
Windows boot disk).  Or you can try using cfdisk as described below.

man cfdisk

DOS 6.x WARNING
       The DOS 6.x FORMAT command looks for some information in the
first sector of the data area of the partition, and treats this
information as more reliable than the information in the partition
table.  DOS FORMAT expects DOS FDISK to clear the first 512 bytes of the
data area of a partition whenever a size change occurs.  DOS FORMAT will
look at this extra information even if the /U flag is given -- we
consider this a bug in DOS FORMAT and DOS FDISK.

       The bottom line is that if you use cfdisk or fdisk to change the
size of a DOS partition table entry, then you must also use dd to zero
the first 512 bytes of that  par-tition  before  using  DOS  FORMAT to
format the partition.  For example, if you were using cfdisk to make a
DOS partition table entry for /dev/hda1, then (after exiting fdisk or
cfdisk and rebooting Linux so that the partition table information is
valid) you would use the command "dd if=/dev/zero of=/dev/hda1 bs=512
count=1" to zero the first 512 bytes of the partition. Note:

       BE EXTREMELY CAREFUL if you use the dd command, since a small
typo can make all of the data on your disk useless.

-- 
Scott Tiret <stiret@oneredshoe.net>

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