FP2007 and HORM

[Michael Bate]

I am using HORM with FP2007. Previously I used HORM with SP2. I'm a
bit confused about the following:

- The Enhanced Write Filter now has an option to "Enable HORM" I'm not
clear what this does, other than create the RESMANY.DAT file.

- EWFMGR now has options to active and deactiveate HORM. These options
do not erase or create RESMANY.DAT and I believe they do not erase or
create the hibernation file (hiberfil.sys).

Previous to FP2007, you activated HORM by enabling hibernation, enabling
the write filter, and creating RESMANY.DAT. That was all it took
(unless I'm forgetting something). Is there something else going on
behind the scenes in FP2007?

-Michael Bate

 

[Sean Liming \(eMVP\)]

Basically you are correct.

1. The EWF option saves the time in having to create a resmany.dat file. You
still have to enable Hibernation in the ACPI computer component. The EWF
option doesn't do this automatically.
2. EWFMGR option allows you to turn off HORM without having to commit the
current session.

Regards,

Sean Liming
www.sjjmicro.com / www.seanliming.com
XP Embedded Book Author - XP Embedded Advanced, XP Embedded
Supplemental Toolkit

 

[KM]

Michael,

Please see my comments inline...

I am using HORM with FP2007. Previously I used HORM with SP2. I'm a bit
confused about the following:

- The Enhanced Write Filter now has an option to "Enable HORM" I'm not
clear what this does, other than create the RESMANY.DAT file.

Well, it pretty does what is required - create the .dat file. Only
difference in FP2007 vs SP2 is that the file is now called HORM.DAT. I guess
it was renamed to reflect the actual purpose and create less confusion
the HORM.DAT file (which is actually goes from EWF component file resources)
is not a zeros-ze file (4K) but seems to have a dummy content. New EWF ntldr
of FP2007 does refer to HORM.DAT (not resmany.dat) but I guess it still
works the same way - the presense of the file in root directory of the boot
partition is what matters for the loader.

- EWFMGR now has options to active and deactiveate HORM. These options do
not erase or create RESMANY.DAT and I believe they do not erase or create
the hibernation file (hiberfil.sys).

New commands of ewfmgr are much easier to use now. No need to mess with the
files or reboots.
Once you enabled HORM for your image you can activate or deactivate HORM
immediately and no reboot required.

Quite frankly, I didn't have enough time to look very carefully at the new
loader and what it does in FP2007 - not sure how it deals with the
hiberfil.sys file header (first 4K). Things to do soon, though.

Previous to FP2007, you activated HORM by enabling hibernation, enabling
the write filter, and creating RESMANY.DAT. That was all it took (unless
I'm forgetting something). Is there something else going on behind the
scenes in FP2007?

You still need to enable hiubernation in TD or at run time manually :-(
Also, dont' forget to add "Disk Dump Drivers" component to your config to
support hibernation feature.

Regards,
KM

 

[Michael Bate]

Sorry to take so long to get back on this topic, but I have
ever-shifting priorities.

KM and Sean gave me a lot of good information. I had no idea that
HORM.DAT replaced RESMANY.DAT. Is that documented anywhere in the
Microsoft Help?

My system is currently hibernating with no problem, and I never added
"Disk Dump Drivers" to my configuration. "Disk Dump Drivers" is a low
visibility component that according to Target Designer Component Help,
adds the file diskdump.sys to your configuration. The help claims, as
you do, that you cannot hibernate without it. Yet that file is nowhere
in my OS image, that hibernates fine.

Does anyone know what is going on?

Thanks,
Michael

 

[KM]

Michael,

Well, I remember the diskdump driver was required to get system crash dumps working for sure.

I've been under impression the system hibernates by the same route - it is dumping the RAM content to disk by using the same driver.
The diskdump driver takes its part here instead of scsiport driver. It is just limited version in functionality.

Not sure how the hibernation is working for you without that driver. When I am back to my desk I may try to test this on FP2007 to
see if the above is still true.