Re: Symantec Ghost Console Client under Dosemu

Re: Symantec Ghost Console Client under Dosemu

[Stas Sergeev]

Hello.

Per von Zweigbergk wrote:
> Dosemu monopolising the network card as well as the hard drive will not 
> be a problem, since the only thing needing those resources would be 
> Ghost itself, which runs under Dosemu.
Wouldn't it be better to just stop using
linux and install only DOS then? Why do
you need linux and dosemu that is monopolizing
everything and merely turn yours linux box into
a DOS box?

> So, as I see it there are no 
> theoretical reasons why this won't work.
I wouldn't take that lightly what Bart said.
Dosemu allows the progs to use protected mode
only via DPMI, which can't be expected from
Ghost. Now the question is: does the Ghost
use protected mode? If the answer is "yes",
then you are in a deep troubles.

> First of all, where can I find the DOS side of the packet driver? As 
> I've understood it, there needs to be a EXE on the DOS side containing 
> a packet driver for the particular network card.
No. $_pktdriver=(on) does everything for you.

> Is this a specialized driver 
> that the Dosemu project provides
Yes, and you don't need to care about launching
it - it is built-in.

> Second, is there simple way to detect if a BAT file is running under 
> Dosemu?
Dosemu have the set of helper commands.
You have to study these as they are providing
some very usefull functionality.
Use "isemu" command for detecting dosemu.
Though if your dosemu is not recent CVS, its
helper commands may lock up your machine if
started not under dosemu. If that's the problem,
you'll have to upgrade your dosemu and all its
commands from CVS.

Re: Symantec Ghost Console Client under Dosemu

[Per von Zweigbergk]

On Sat, 2 Oct 2004, Stas Sergeev wrote:

> Per von Zweigbergk wrote:
> > Dosemu monopolising the network card as well as the hard drive will not 
> > be a problem, since the only thing needing those resources would be 
> > Ghost itself, which runs under Dosemu.
> Wouldn't it be better to just stop using
> linux and install only DOS then? Why do
> you need linux and dosemu that is monopolizing
> everything and merely turn yours linux box into
> a DOS box?

Except the network card I have doesn't have Linux drivers. That's the main 
reason I'm going to be trying this experiment.

> > So, as I see it there are no 
> > theoretical reasons why this won't work.
> I wouldn't take that lightly what Bart said.
> Dosemu allows the progs to use protected mode
> only via DPMI, which can't be expected from
> Ghost. Now the question is: does the Ghost
> use protected mode? If the answer is "yes",
> then you are in a deep troubles.

I don't know yet, but I will check as soon as I find the time.

-- 
Per von Zweigbergk <pvz@e.kth.se>

Re: Symantec Ghost Console Client under Dosemu

[Per von Zweigbergk]

On Sat, 2 Oct 2004, Per von Zweigbergk wrote:

> On Sat, 2 Oct 2004, Stas Sergeev wrote:
> 
> > Per von Zweigbergk wrote:
> > > Dosemu monopolising the network card as well as the hard drive will not 
> > > be a problem, since the only thing needing those resources would be 
> > > Ghost itself, which runs under Dosemu.
> > Wouldn't it be better to just stop using
> > linux and install only DOS then? Why do
> > you need linux and dosemu that is monopolizing
> > everything and merely turn yours linux box into
> > a DOS box?
> 
> Except the network card I have doesn't have Linux drivers. That's the main 
> reason I'm going to be trying this experiment.

Correction: I meant the card doesn't have DOS drivers. Sorry for the
confusion. (I should proofread my e-mails better.)

-- 
Per von Zweigbergk <pvz@e.kth.se>

Re: Symantec Ghost Console Client under Dosemu

[Stas Sergeev]

Hello.

Per von Zweigbergk wrote:
>> Wouldn't it be better to just stop using
>> linux and install only DOS then?
> Except the network card I have doesn't have Linux drivers. That's the main 
> reason I'm going to be trying this experiment.
Looks like the reversed logic to me, grrr.
If you don't have the linux drivers, then
you are of no hopes running it under Linux,
no matter whether you use dosemu or not.
So, you have the DOS drivers, but no linux
drivers, and that makes your argument for
trying it under linux instead of the DOS?

Re: Symantec Ghost Console Client under Dosemu

[Stas Sergeev]

Hello.

pvz@e.kth.se wrote:
> 1) The MAC address of seen by Ghost in DOS needs to be the same as the 
> physical MAC address, and outgoing packets need to have the MAC address of the 
> physical card.
This is possible, although in that mode
dosemu will monopolize your NIC so that
Linux will no longer use it. This also
requires root. The setup for that is simple:
$_pktdriver=(on)
$_vnet=""
$_netdev="eth0"
Though right now the comments in the dosemu.conf
do not suggest $_vnet can be set to "", it only
says about "dosnet" and "tap". This needs to be
fixed to avoid confusion.
Though keep in mind that Ghost under dosemu will
see only the packet interface, not your card. Ghost
supports the packet driver interface, so this should
be not a problem.

> Dosnet, but this should probably be doable.
Forget about dosnet. It is going to be removed.
If you want dosemu to cooperate with your linux
box wrt networking, use TAP. In that case though
the DOS box will have the different (virtual) MAC,
not the real one.

> 2) Ghost will probably need to be able just to access the hard drive 
> directly
As you know, this is no longer supported.

> I can't seem to find if this is possible in current versions in
> the HOWTO, although I seem to have seen indications that this at least 
> used to be possible in earlier versions.
So it was removed. Not really, just disabled in
global.conf, AFAICS. You can easily get it back
with a trivial hack in global.conf (or even
without any hacks at all).
But I don't think it really had to be removed.
People used it on their own risk, it worked for
them, and suddenly it is not any more.
Of course it is horribly unsafe, but not so much
when your drive is not mounted at all, and it was
available only for root, and being root you can
corrupt your drives if you want to. So the removal
probably have to be reconsidered. And if you'll
manage to get the positive results, that will
probably be a good motivation.

> I'd also like to know if any of the components, specifically Dosnet
Forget it.

> direct
> hard disk access is known to be particularilly flaky.
To my own expirience (when it was still there) -
it was not flakey. It was not perfect either (I had
a few progs that worked with partition access, but
not with wholedisk access), but it never, never ever
costed me a single byte of lost info, even though I
tried it with accessing the same space from within
linux at the same time, and other weird things. And
I have not seen any negative comments about it here
either, although probably they took place before I
subscribed. Yet I've seen (rightfull) complains when
it was removed. This all doesn't look right to me.
At least dosemu could check whether the drive is in
use (any partition is mounted), and allow the access
only if it is not. Or explicitly ask the confirmation
for allowing it to corrupt the data...

Re: Symantec Ghost Console Client under Dosemu

[Bart Oldeman]

On Thu, 30 Sep 2004, Stas Sergeev wrote:

> So it was removed. Not really, just disabled in
> global.conf, AFAICS. You can easily get it back
> with a trivial hack in global.conf (or even
> without any hacks at all).

you don't even need global.conf -- global.conf syntax also works in
dosemu.conf.

$_hdimage = ""
disk {wholedisk "/dev/hda"}

in dosemu.conf (or root's ~/.dosemurc if root runs dosemu) does
the job. Though I had to use $_vbootfloppy (a floppy image) to boot, since
DOSEMU doesn't like GRUB in the MBR (tries to go to protected mode
itself).

It was never really removed, just never supported in the new dosemu.conf
syntax (Feb 98, 0.97.2, over two years before I was involved). But right
now there isn't much of a reason anymore; as it used to be dosemu was
suid-root by default and any user could get the wholedisk (depending on
dosemu.users), now it solely depends on the permissions of /dev/hda.

So I'm not opposed to it, just too lazy to add the support to dosemu.conf
;)

Bart

Re: Symantec Ghost Console Client under Dosemu

[Per von Zweigbergk]

Thanks to Stas Sergeev for the very helpful post, and to Bart Oldeman 
for the supplementary comments. Both posts have been very helpful.

Dosemu monopolising the network card as well as the hard drive will not 
be a problem, since the only thing needing those resources would be 
Ghost itself, which runs under Dosemu. So, as I see it there are no 
theoretical reasons why this won't work.

I'm going to try this as soon as possible. I'll see if I get the time 
to do it tomorrow -- and then I'll probably just launch a Knoppix CD or 
something and see if I can get Dosemu installed under that.

If results of that are favorable, I'm going to try running some 
different imaging tasks, and network operations, to see if it'll work.

If that in turn works, I'll start investigating the possibility of 
creating or modifying some form of custom Linux distribution to do what 
I want.

A few question marks still remain to be straightened though.

First of all, where can I find the DOS side of the packet driver? As 
I've understood it, there needs to be a EXE on the DOS side containing 
a packet driver for the particular network card. From the point of view 
of Ghost, I'll need some sort of packet driver for DOS in order for 
Ghost to see the emulated network card. Is this a specialized driver 
that the Dosemu project provides, and/or does Dosemu just emulate some 
popular network card, allowing me to use one of Ghost's supplied packet 
drivers?

Second, is there simple way to detect if a BAT file is running under 
Dosemu? One method that comes to mind would be if the DOS side of the 
packet driver produces useful return codes if not run under Dosemu. I 
need to make an ugly hack whereby the same partition is booted twice, 
once on the bare metal just to run Loadlin on the kernel, and the 
second time under Dosemu. This is because I  don't want to step on how 
Ghost handles bootable flags and other doodads when invoked over the 
network. Best not to be looking for more trouble than I'm already in. 
:-) Suggestions on this point would be nice, but if nothing else, I 
should be able to pull this off using some hacks whereby control files 
are created, checked and destroyed -- but better ideas would be 
appreciated.

-- 
Per von Zweigbergk <pvz@e.kth.se>

Symantec Ghost Console Client under Dosemu

[pvz]

I administer a few Microsoft Windows machines at work. We have recently
purchased Symantec Ghost Corporate Edition 8.0 for centralized disk image
administration. However, I failed to consider that Ghost requires a
DOS-compatible network card when performing remote imaging tasks and other
similar stuff.

To compensate for this, I thought it might be worth trying to modify Norton
Ghost's special "boot partition", which is basically just an installation of
IBM PC-DOS on a seperate partition, bootstrapped with drivers and the Ghost
executable.

This boot partition could be modified to use some form of Linux -- probably a
customized distribution, or something based on existing boot disks depending on
complexity. This would allow me to use Dosemu in single user mode to run Ghost
Console Client under Dosemu, conveniently launched through some startup
scripts. I would use Dosnet to allow Ghost to access the network card through
Linux drivers. The cards in question do have Linux drivers which I have tried
and verified that they work using Knoppix.

In order for this to work, I have to be able to do the following:

1) The MAC address of seen by Ghost in DOS needs to be the same as the physical
MAC address, and outgoing packets need to have the MAC address of the physical
card. This is because the Ghost Console identifies computers via their MAC
address, and will probably freak out otherwise. I haven't looked closely into
Dosnet, but this should probably be doable. Any info on doing this specifically
would be helpful.

2) Ghost will probably need to be able just to access the hard drive directly --
without any form of file system redirection drivers or partition table
remapping or other forms of hacks. I don't need to be able to access the hard
drive from Linux itself -- I can happilly just make a system that does what I
want and load it as an initrd ramdisk. (Possibly also using loadlin or other
evil things.) I can't seem to find if this is possible in current versions in
the HOWTO, although I seem to have seen indications that this at least used to
be possible in earlier versions.

3) Ghost Console Client has to be runnable under Dosemu. While this setup will
probably be wildly unsupported from Symantec's end, and I haven't seen anybody
else on the Internet doing this, I'll be in uncharted terrirory, but I won't
really be able to test this until I solve problems 1 and 2. I'm not really an
expert programmer when it comes to the sort of code Dosemu is made of, but I
might be able to iron out a few wrinkles and hack a few patches if it proves to
be necessary.

I'd like to hear some opinions on my chances of pulling something like this off.
Also, some pointers on my questions above would also be immensely helpful.

I'd also like to know if any of the components, specifically Dosnet and direct
hard disk access is known to be particularilly flaky. Potential data loss is
not an issue, since image files will be backed up to a safe location and all
"important" data is stored remotely on a Samba server running FreeBSD anyway.

Finally, although offtopic, if anybody has any alternate suggestions for solving
my problem, I'd appreciate to receive some of those as well, as long as those
replies are kept off-list in order to keep the mailing list on topic.

Thanks in advance!

Per von Zweigbergk <pvz@e.kth.se>