Moxa V2201-E4-T [18/61] File based write filter

V2201 Series Windows Software Enabling Embedded Filters

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3. In the Enhanced Write Filter Configuration screen, select a drive volume; then, select an option from the

Pending Command drop-down list:

• No Command

• Disable: Disables EWF on the selected drive. You will need to select the “commit” checkbox and reboot

the system for changes to take effect.

• Commit: Writes all current system changes to the hard drive.

• Commit and Disable Live: Writes all current data and changes to the system, and also turns off EWF

on the selected drive (so that all future data and system changes will also be committed to the drive).

The system does not automatically reboot if you select this option.

NOTE

For detailed

information, go to the Microsoft website at

http://msdn.microsoft.com/en

-us/library/ff794092(v=winembedded.60).aspx.

File-Based Write Filter

This section describes how to use the File-Based Writer Filter (FBWF). Note that when Enhanced Writer Filter is

enabled, the File-Based Writer Filter function will not work.

According to Microsoft:

“File-Based Write Filter (FBWF) allows the Windows Embedded platform to maintain the appearance of read

and write access on 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. Used in this context, an overlay is similar 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.”

FBWF supports an advanced ESF feature, which allows users to specify which directory to write data to. The

default directory is c:\temp. The advanced feature allows you can read/write data to disk without committing

an action.