Need help with incorrectly nested partitions

[Svante Signell]

On Sat, 2010-08-21 at 11:11 +0200, Svante Signell wrote:
> On Fri, 2010-08-20 at 11:30 +0200, Vladimir 'φ-coder/phcoder' Serbinenko
> wrote:
> > On 08/20/2010 10:34 AM, Svante Signell wrote:
> > > Installing a new grub version gives the following output:
> > > Setting up grub-pc (1.98+20100804-3) ...
> > > Installing new version of config
> > > file /etc/kernel/postinst.d/zz-update-grub ...
> > > Installing new version of config
> > > file /etc/kernel/postrm.d/zz-update-grub ...
> > > grub-probe: warn: Discarding improperly nested partition
> > > (hd1,msdos3,msdos1).
> > > ...
> > > Found Windows NT/2000/XP on /dev/sda1
> > > ...
> > > /usr/sbin/grub-probe: warn: Discarding improperly nested partition
> > > (hd1,msdos3,msdos1).
> > > Found Microsoft Windows XP Home Edition on /dev/sda2
> > > /usr/sbin/grub-probe: warn: Discarding improperly nested partition
> > > (hd1,msdos3,msdos1).
> > > ...
> > >
> > >
> >    
> > It's only a warning and if you're not supposed to have subpartitions at
> > all then you can just ignore them
> 
> What do you mean with subpartitions? I assume that /dev/sda1 is msdos1
> (vfat) and /dev/sda2 is msdos3 (ntfs) and the warning says that they are
> overlapping? The first partition /dev/sda1 is not of large interest, it
> is the backup part of Windows at /dev/sda2. I don't need sda1 as I don't
> plan to restore the original installation but sda2 is important. Anyway,
> it is very annoying to get this message every tim grub-pc is updated! 
> 
> > > When booting and checking the partitions:
> > > dosfsck 3.0.9, 31 Jan 2010, FAT32, LFN
> > > There are differences between boot sector and its backup.
> > > Differences: (offset:original/backup)
> > >   65:00/01
> > >   Not automatically fixing this.
> > > /dev/sda1: 9309 files, 802467/945032 clusters
> > > done.
> > >
> > >   
> > man dosfsck
> 
> Yes as written below this would be the solution. But do I need to
> rewrite the mbr, an if so I have forgotten how to do that, install-mbr
> or something else related to grub without destroying anything?

So which option should be used???

dosfsck 3.0.9, 31 Jan 2010, FAT32, LFN
There are differences between boot sector and its backup.
Differences: (offset:original/backup)
  65:00/01
1) Copy original to backup
2) Copy backup to original
3) No action
? 1
Perform changes ? (y/n) n
/dev/sda1: 9309 files, 802467/945032 clusters

And then what: install-mbr, grub-install, update-grub or??

Any pointers/documentation/whatever??

Thanks,
Svante