I am developing a volume level upper filter driver, which monitors all write activities on a volume.
Each IRP_MJ_WRITE call is traced into a bitmap file that stores the changes. The bitmap is used to
create an incremental backup of a volume. To have the volume in consistent state we are using VSS
and transfer the changed clusters from the VSS volume.
The problem is, sometime, we are getting corrupted destination volume after copy.
The driver processes the completion of the IOCTL_VOLSNAP_FLUSH_AND_HOLD_WRITES and then will zero out the bitmap file.
Even when there is no activity on the volume, incremental will produce a corrupted target.
The issues are less frequent when we transfer the full MFT.
Is there a point during VSS snapshot procedure when a volume is 100% in sync, meaning the last IRP_MJ_WRITE call
has been traced by my driver?
Thanks in advanced.
I swear we just finished discussing this problem.
Mark Roddy
On Thu, Jan 15, 2009 at 12:11 PM, wrote:
> I am developing a volume level upper filter driver, which monitors all
> write activities on a volume.
> Each IRP_MJ_WRITE call is traced into a bitmap file that stores the
> changes. The bitmap is used to
> create an incremental backup of a volume. To have the volume in consistent
> state we are using VSS
> and transfer the changed clusters from the VSS volume.
> The problem is, sometime, we are getting corrupted destination volume after
> copy.
> The driver processes the completion of the
> IOCTL_VOLSNAP_FLUSH_AND_HOLD_WRITES and then will zero out the bitmap file.
> Even when there is no activity on the volume, incremental will produce a
> corrupted target.
> The issues are less frequent when we transfer the full MFT.
> Is there a point during VSS snapshot procedure when a volume is 100% in
> sync, meaning the last IRP_MJ_WRITE call
> has been traced by my driver?
>
> Thanks in advanced.
>
>
>
>
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