Moxa V2401-LX [34/61] Enhanced write filter

V2401/2402 WinXP User’s Manual Software Configuration

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Enhanced Write Filter

The “Enhanced Write Filter” protects the contents of a volume on the target media volume by

redirecting all writes to another storage location called on overlay. Use the following steps to

enable the Enhanced Write Filter.

1. Type EWFMGR C: to check if the state of the Enhanced Write Filter is Disabled.

2. To enable the filter, type EWFMGR C: -enable.

3. Reboot the system to activate the change.

4. Delete a file on your protected volume and reboot the system; the file you just deleted will

appear.

File Based Write Filter

File-Based Write Filter (FBWF) allows Windows Embedded Standard 2009 to maintain the

appearance of read and write access to write sensitive or read only storage. FBWF makes read and

write access transparent to applications.

Writing to storage media may be undesirable or impossible in embedded devices. FBWF redirects

all writes targeted for protected volumes to a RAM cache called an overlay. In this context, an

overlay can be likened to a transparency overlay on an overhead projector. Any change made to the

overlay affects the picture as seen in the aggregate, but if the overlay is removed, the underlying

picture remains unchanged.