Backup and Restor MBR

[Hadders]

Mike McCarty wrote:
> Aaron Konstam wrote:
>> On Sun, 2006-12-10 at 07:01 +0530, Vivek J. Patankar wrote:
>>
>>> On 12/10/06, Hadders <fedora at workingwithit.com> wrote:
>>>
>>>> I'm going to install Vista (dual-boot) and was wondering if it was 
>>>> easy
>>>> to just back it up rather than running grub?
>>>
>>> # dd if=/dev/hda of=/path/filename bs=512 count=1
>>
>> No, No, NO. The MBR is only the first 446 bytes of block 0. The rest is
>> the partition table. I assume you don't want to rewrite the partition
>> table.
>
> The MBR is the Master Boot Record, which is 512 bytes long.
> The MBR comprises three parts
>
> 1. Code
> 2. Partition Table
> 3. Boot Record Marker (AA 55)
>
> No part of the MBR may be read or written without reading
> or writing all of it. Discs are, after all, BLOCK DEVICES
> which cannot transfer any amount less than a block (sector).
>
> I don't like to presume about what other people do. (BTW, you
> might investigate the difference in meaning between "assume",
> and "presume".) If he states he wants to save and restore his
> MBR, then I answer accordingly. If I have a question about what
> his goals are, then I ask.
>
> If you are going to give such strong corrections and advice, you
> ought at least to be correct.
>
> Saving the MBR should be done in its entirety. Whether one wants
> to preserve the PT portion of the MBR when rewriting it on disc
> later is a decision to be made at that time. Not saving the original
> PT portion of the MBR is folly.
>
> Mike
Thanks for that info.  I'm after the lot. I intend to back it up and 
then restore it after I install Vista, which of course, will nail the 
MBR during install.

Hadders