[Date Prev][Date Next] [Thread Prev][Thread Next] [Date Index] [Thread Index]

Re: where does grub put the MBR?




On Wed, 3 May 2006, Hugo Vanwoerkom wrote:

> Roberto C. Sanchez wrote:
> > Hugo Vanwoerkom wrote:
> >> Hi,
> >>
> >> Is there a way to know *for sure* where grub puts the MBR? (No setup
> >> command)

yes...

> > Well the MBR, is always in the same place.  It is *always* the first 512
> > bytes on the physical disk.

the MBR is the first 446 bytes of each partition ....
	16 bytes for each of the 4 primary partition
	 2 bytes for the boot flag

and if you have more than one partition, the "boot record" is the
first 448 bytes of each primary primary

>  Now, what I think you want to ask is,
> > "where does grub install itself?"  As to that, I don't know, other than
> > scanning the disk and its partitions to see.  Though, I am not certain
> > how one would do that.

grub stage1 or lilo, etc is loaded by the bios into 0x7C00
grub stage1.5 is loaded by the bios into 0x8K

> And what would I look for?

you don't ...  but if you insist... use a diskeditor to read the contents
of any random cylinder/head/sector "to look for" stuff

c ya
alvin



Reply to: