EWF with compressed NTFS on CompactFlash

  • Thread starter Thread starter Paolo Dematteis
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Paolo Dematteis

Hi, all
do anyone have some experience using EWF (XPe SP2) on CompactFlash with a
compressed NTFS file system?
I tried this solution:
- 256 MB PQI industrial CF
- compressed NTFS file system
- XPe SP2 image with RAM/REG EWF enabled
- a custom shell (my application)
- "ewfmgr -commit" before the shutdown each time the user exit the
program correctly (to save all the pending data)
Normally this works fine, but in some case I experienced a registry
corruption causing a blue screen on next boot.
Any idea?
Thanks.
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If I understand you "commit" just before shutdown.
Perhaps sometimes there is no time to write all data and system files get
corrupted.
I suggest to try doing "commit" at a safe time far from shutdown.
Otherwise if system corrupts only after a "commit" issued anytime the fault
is caused by an application.
I prefer to protect system partition and enable EWF only for maintenance,
all application data are written to a unprotected partition.
Regards Raffaele
 
Paolo ,

How exactly do you perform the shutdown?

Also, it is not a good practice to commit the entire EWF overlay on CF frequently. You may end up with some corrupted blocks and
data on the flash.
If doing the commit is only for purpose of your app saving its data, you may rather want to think about using EWF file only commit
(to many limitations on the file size and location though) or, the best for your system scenario, to move to use FBWF component from
FP2007 instead of EWF. With FBWF you will be able to protect the entire system but still have certain files unprotected. This way
you wouldn't be needing to commit changes in the entire overlay and touch registry hives.
 
Hi,

I perform the shutdown using the API "ExitWindowsEx (EWX_SHUTDOWN |
EWX_FORCE | EWX_POWEROFF)", but in many situations the power-off is not
performed as I use an AT power supply.
Just before this command I run the "ewmgr -commit" using a Shell command in
a VB6 application.
I tried this solution to be p&p with the previous XPe distributions, without
the EWF protection, that use only one partition on the CF (I made a patch to
add the EWF driver and related registry setting at runtime).
I use a -commit just before the shutdown because I noticed that after the
commit the CF become unprotected. Is there a way to be sure that the commit
has completed the write operation and than perform a safe shutdown? I need
to preserve changed registry data an some application related files like a
DB and a log.
In the future I think the best solution is to use two different partitions,
but I need to find the best on for the released products.

Thanks
 
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