Re: [users] dd question
"Martin F. Krafft" wrote:
>
> also sprach Joerg Johannes (on Sun, 01 Jul 2001 02:09:49PM +0200):
> > 1.) Just to be sure:
> > dd if=/dev/zero of=/dev/sda1
> > will overwrite any data on sda1 with zeroes, but leave sda2, sda3 and
> > the mbr untouched?
>
> yes.
>
> > 2.) To backup my mbr I do
> > dd if=/dev/sda of=/flopyy/mbr.sda bs=512 count=1
> > and to put it back
> > dd if=/floppy/mbr.sda of=/dev/sda bs=512 count=2
>
> why count=2 when writing back? count=1 should do.
>
OOPS, typo, should not happen when really doing it...
> > Will this be enough to get lilo back after windos new install?
>
> why not just rerun lilo?
Good idea, but would need rescue disc wiht xfs-enabled kernel for it, so
this one must do it
>
> > 3.) During all this dd'ing, /dev/sda must be *completely* unmounted?
>
> no, /dev/sda1 *should* be unmounted while dd'ing over it. but since
> you are writing 0's, there's not much else that can break if you'd
> leave it mounted. but sure, unmount the entire thing!
>
> martin; (greetings from the heart of the sun.)
> \____ echo mailto: !#^."<*>"|tr "<*> mailto:"; net@madduck
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