GRUB 2

[Loïc Grenié]

2011/3/2 Colin Law <clanlaw at googlemail.com>:
> On 2 March 2011 08:56, Loïc Grenié <loic.grenie at gmail.com> wrote:
>> ...
>>    The problem is that one every three boots must be on XP the two
>>  others on Linux. The idea is that you can remotely reboot the
>>  machine and after at most three attempts you get XP.
>
> Is the *real* problem that you would like to decide remotely which OS
> to boot into next?
>
> It is easy enough when in Ubuntu to decide that you wish to boot into
> XP next by editing /etc/default/grub and running sudo update-grub.
> This could be done via a script so that manual edit is not required
> each time.
> The problem arises when in XP and you wish to boot into Ubuntu.  It is
> possible to access an ext3 file system from Linux, see
> http://www.go2linux.org/access-ext2-ext3-from-xp for example, there
> may be other possibilities, but so it would be possible to edit
> /etc/default/grub, but I don't think it would be possible to run
> update-grub so this route will not work.  You could, however, edit
> /boot/grub/grub.cfg to achieve the same result.  One should not
> normally edit this file as it is generated by update-grub, but in this
> case I think there is a valid argument for so doing.  In fact if this
> route is taken to switch back to Ubuntu, since /etc/default/grub has
> not been changed, then to get from Ubuntu back to XP it is only
> necessary to run sudo update-grub to restore /etc/default/grub back to
> its normal state.
>
> So the conclusion:
> 1. Install tools to allow access to Ubuntu partition from XP
> 2. In Ubuntu edit /etc/default/grub so that the default is XP.
> 3. Write a windows script that edits /boot/grub/grub.cfg so that the
> next boot will be into Ubuntu.
> 4. When running Ubuntu, to set next boot to XP simply run sudo
> update-grub to restore /etc/default/grub to boot into XP

    Accessing ext2/ext3 partition from Windows sounds frightful...
  I'd not dare the risk. It's much easier to use

sudo grub-reboot 3

  (where 3 is the number of the entry for windows).

    I should have said that from day 1.

      Sorry for the delay,

          Loïc