Booting from virtual device...

NTFSD
1

Hi,

This is the scenario. I have an image of a WinNT
installaion. I want to boot from it - boot from a
virtual device.

I write the boot code and a ‘driver’ that creates this
virtual hard-disk for the os to boot from.

Now is this possible? I am not very sure if it is. Is
it possible to have a ‘driver’ like this that can work
with Windows NT/XP/2K??

Could you guys tell me what you think about it? Any
ideas at all would be welcome.

Thanks in advance!

Regards,
Manoj

Yahoo! India Matrimony: Find your partner online.
Go to http://yahoo.shaadi.com

2

Answer to Ur question would be a big no. Bootstrapping is usually
multistage, but as U explained the image would be in a virtual drive ( then
how would the loader would load the system from virtual drive, that is very
dependent on the system itself). For the same reason I think you can not
load it over the network…

There are multiple places you can look at for more information on PC boot
steps, but I strongly doubt that what you explained here is possible… BIOS
would jump to fixed location, that is a mini strapper, that would eventually
load the Loader (at this perticular stage, the notion of disk is not driver
related, so virtual device notion is not there yet …)

-prokash

----- Original Message -----
From: “Manoj Paul Joseph”
To: “Windows File Systems Devs Interest List”
Sent: Saturday, October 25, 2003 6:34 AM
Subject: [ntfsd] Booting from virtual device…

> Hi,
>
> This is the scenario. I have an image of a WinNT
> installaion. I want to boot from it - boot from a
> virtual device.
>
> I write the boot code and a ‘driver’ that creates this
> virtual hard-disk for the os to boot from.
>
> Now is this possible? I am not very sure if it is. Is
> it possible to have a ‘driver’ like this that can work
> with Windows NT/XP/2K??
>
> Could you guys tell me what you think about it? Any
> ideas at all would be welcome.
>
> Thanks in advance!
>
> Regards,
> Manoj
>
> ________________________________________________________________________
> Yahoo! India Matrimony: Find your partner online.
> Go to http://yahoo.shaadi.com
>
> —
> You are currently subscribed to ntfsd as: xxxxx@garlic.com
> To unsubscribe send a blank email to xxxxx@lists.osr.com
>
>

3

Impossible using a driver; a driver assumes there is an OS to load the
driver. It is a chicken and egg thing.

If this is for a product you working on, please contact me in private; I
know how to do this, but it requires something more than just an NT
device driver.

Jamey

-----Original Message-----
From: xxxxx@lists.osr.com
[mailto:xxxxx@lists.osr.com] On Behalf Of Manoj Paul Joseph
Sent: Saturday, October 25, 2003 6:35 AM
To: Windows File Systems Devs Interest List
Subject: [ntfsd] Booting from virtual device…

Hi,

This is the scenario. I have an image of a WinNT
installaion. I want to boot from it - boot from a
virtual device.

I write the boot code and a ‘driver’ that creates this
virtual hard-disk for the os to boot from.

Now is this possible? I am not very sure if it is. Is
it possible to have a ‘driver’ like this that can work
with Windows NT/XP/2K??

Could you guys tell me what you think about it? Any
ideas at all would be welcome.

Thanks in advance!

Regards,
Manoj

Yahoo! India Matrimony: Find your partner online.
Go to http://yahoo.shaadi.com

You are currently subscribed to ntfsd as: xxxxx@storagecraft.com
To unsubscribe send a blank email to xxxxx@lists.osr.com

4

— Prokash Sinha wrote:

> load the Loader (at this perticular stage, the
> notion of disk is not driver
> related, so virtual device notion is not there yet
> …)

Maybe my usage of the term ‘driver’ was mis-leading.
I am not talking about a NT driver.

Since the boot code in mine, I can hook the IRSs…
But once the OS switches to protected mode,(I would
have to let the OS do this, right?), I loose
control…
Am I wrong??

Regards,
Manoj

________________________________________________________________________
Yahoo! India Matrimony: Find your partner online.
Go to http://yahoo.shaadi.com

5

> Subject: Booting from virtual device…

From: =?iso-8859-1?q?Manoj=20Paul=20Joseph?=

> Date: Sat, 25 Oct 2003 14:34:49 +0100 (BST)
> X-Message-Number: 2
>
> Hi,
>
> This is the scenario. I have an image of a WinNT
> installaion. I want to boot from it - boot from a
> virtual device.
>
> I write the boot code and a ‘driver’ that creates this
> virtual hard-disk for the os to boot from.
>
> Now is this possible? I am not very sure if it is. Is
> it possible to have a ‘driver’ like this that can work
> with Windows NT/XP/2K??
>
> Could you guys tell me what you think about it? Any
> ideas at all would be welcome.
>
> Thanks in advance!
>
> Regards,
> Manoj

Surely you can do this by:
still have c:\boot.ini and c:\ntldr on a regular fat or ntfs volume,
but like d:\Windows in your image
have your virtual disk driver be a scsi miniport driver, copy it to
c:\ntbootdd.sys, making the appropriate scsi entry in boot.ini
merging your virtual image into the driver

- Jay

6

It seems like U r trying to have your own boot loader, that would load NT os
and handover the execution !!!. So we can safely assume that U are not
talking about virutal driver in the classical(defined sense) !!. BTW: if
this be the case there might be solutions out there that you might have to
search for, for example the PC vendors often do this kind of stuff for their
recovery CDs !!

When you say that once you switched to protected mode, OS should take
control. And you loose control, yes that is true, since the ISRs you have
(as well as your boot loader) is running in real mode ( address range 1MB
with A20 line on ). BUT MY FIRST QUESTION IS THEN, YOU HAVE ALREADY BROUGHT
IN THE OS or a part of it, and overlaid, otherwise how do you pass control
to the _start of the OS …

If you dont happen to have these information(s) already , pls look at :-

—Intel site for OS bring up code, I might have somewhere that I can dig
and send to you.

— A book called 32-bit OS by Richard Burgess does have the answer to your
current question.

— VM design and Implementation book by Bill Blunden, this is very much in
spirit of VMware…

— Certainly MS or anyone did it already ( Jamey Kerby, for example) would
be able to give you more filtered and to the point answer(s).

-prokash

----- Original Message -----
From: “Manoj Paul Joseph”
To: “Windows File Systems Devs Interest List”
Sent: Saturday, October 25, 2003 9:12 PM
Subject: [ntfsd] Re: Booting from virtual device…

> — Prokash Sinha wrote:
>
> > load the Loader (at this perticular stage, the
> > notion of disk is not driver
> > related, so virtual device notion is not there yet
> > …)
>
> Maybe my usage of the term ‘driver’ was mis-leading.
> I am not talking about a NT driver.
>
> Since the boot code in mine, I can hook the IRSs…
> But once the OS switches to protected mode,(I would
> have to let the OS do this, right?), I loose
> control…
> Am I wrong??
>
> Regards,
> Manoj
>
> ________________________________________________________________________
> Yahoo! India Matrimony: Find your partner online.
> Go to http://yahoo.shaadi.com
>
> —
> You are currently subscribed to ntfsd as: xxxxx@garlic.com
> To unsubscribe send a blank email to xxxxx@lists.osr.com
>
>

7

— Jamey Kirby wrote:
> Impossible using a driver; a driver assumes there is
> an OS to load the
> driver. It is a chicken and egg thing.
>
> If this is for a product you working on, please
> contact me in private; I
> know how to do this, but it requires something more
> than just an NT
> device driver.

Hi Jamey,

Yes I am thinking of taking up a project. Could you
help me out??
Any help would be appreciated.

Regards,
Manoj

________________________________________________________________________
Yahoo! India Matrimony: Find your partner online.
Go to http://yahoo.shaadi.com

8

Manoj,

Take a look at the Technology Overview on www.sureboot.com. I believe
the SureBoot bootable CD/DVD feature does exactly what you are
suggesting by booting and running Windows 2K/Xp from a virtual hard
disk image located on a CD or DVD.

…John

On Sat, 25 Oct 2003 14:34:49 +0100 (BST), Manoj Paul Joseph
wrote:

>
>Hi,
>
>This is the scenario. I have an image of a WinNT
>installaion. I want to boot from it - boot from a
>virtual device.
>
>I write the boot code and a ‘driver’ that creates this
>virtual hard-disk for the os to boot from.
>
>Now is this possible? I am not very sure if it is. Is
>it possible to have a ‘driver’ like this that can work
>with Windows NT/XP/2K??
>
>Could you guys tell me what you think about it? Any
>ideas at all would be welcome.
>
>Thanks in advance!
>
>Regards,
>Manoj
>
> ________________________________________________________________________
>Yahoo! India Matrimony: Find your partner online.
>Go to http://yahoo.shaadi.com
>

9

Hi guys,

– jayk wrote:
> > Subject: Booting from virtual device…
> > From: Manoj Paul Joseph

> > Date: Sat, 25 Oct 2003 14:34:49 +0100 (BST)
> >
> > Hi,
> >
> > This is the scenario. I have an image of a WinNT
> > installaion. I want to boot from it - boot from a
> > virtual device.
> >
> > I write the boot code and a ‘driver’ that creates
> > this virtual hard-disk for the os to boot from.
> >
> > Now is this possible? I am not very sure if it is.
> > Is it possible to have a ‘driver’ like this that
> > can work with Windows NT/XP/2K??
> >
> > Could you guys tell me what you think about it?
> > Any ideas at all would be welcome.
> >
> > Thanks in advance!
> >
> > Regards,
> > Manoj
>
> Surely you can do this by:
> still have c:\boot.ini and c:\ntldr on a regular
> fat or ntfs volume,
> but like d:\Windows in your image
> have your virtual disk driver be a scsi miniport
> driver, copy it to
> c:\ntbootdd.sys, making the appropriate scsi entry
> in boot.ini
> merging your virtual image into the driver
>
> - Jay

Hi,

I have some queries regarding this scsi miniport
driver.

1. Since it (ntbootdd.sys) is loaded very early in the
boot-up process, could I still debug it using WinDbg?

2. Would it be regular miniport driver? Any gotchas?

3. To read from a IDE hard disk (for the virtual drive
image), could I call the IDE driver? Or would I have
to resort to using the BIOS or resort to programming
the IDE controller?

Thanks!
Manoj
PS: Cross posting to ntdev and ntfsd

________________________________________________________________________
Yahoo! India Matrimony: Find your partner online.
Go to http://yahoo.shaadi.com