[Nottingham] Dual Boot - Windows updates and Linux boot failures

[Michael Quaintance]

On Tue, Nov 26, 2013 at 1:56 PM, David Aldred <davidaldred at gmail.com> wrote:
> On 26 November 2013 17:44, Jason Irwin <jasonirwin73 at gmail.com> wrote:
>>
>> On 26/11/13 17:32, David Aldred wrote:
<snip>
>> > Is this expected behaviour?  And how is the presence of an incomplete
>> > Windows update stopping Linux booting in these circumstances?
>> Quite possibly down to Windows flagging that it needs to reboot to
>> complete update and this through GRUB2 off.
>> But that's just a total guess on my part.
>
>
> It was the sort of thing I was guessing too, but it implies an actual
> recognition of some sort by Windows that Linux exists on the machine, which
> is unusual!
>

I was thinking along the lines of Jason's suggestion but my assumption
was the exact opposite implication than the one you describe. I was
thinking that Windows modifies the MBR with something for the Windows
boot process to recognize and take a different action on with
absolutely no regard to any other operating systems that might be
present.

I'm confused in the first instance why you would want to promote a
working VM to a multiboot partition but that's mainly because I've
been bitten by this sort of thing so often that I only run MS Windows
in a VM nowadays (excepting my work laptop where I have no choice).
I've not found anything where the VM is a problem, even external
hardware is almost all USB nowadays and USB passthrough works fine for
everything I have needed it for.

The last time this bit me was under Windows XP where my laptop was set
to default to Ubuntu but had XP as well (mainly for Microsoft Office
at the time). When working one night in XP, I left it running then
automatic updates forced a reboot and it tried to reboot into Ubuntu
because I was not at the keyboard (I was sleeping at the time) when I
woke in the morning, I had forgotten that I had left it in Windows the
night before and was really confused why Ubuntu had borked. I spent
_so_ long trying to diagnose the seemingly broken Ubuntu when it was a
partial Windows update that was the cause. Since then, Windows in a VM
for me.

-Michael