File-Based Write Filter - Siemens SIMATIC IPC277D Operating Instructions Manual

Advanced device functions

5.3 File-Based Write Filter

5.3 File-Based Write Filter
Purpose and function
Microsoft introduced a second write filter with Feature Pack 2007 for Windows XP
Embedded, namely the File Based Write Filter (FBWF).
In contrast to EWF, which protects partitions based on sectors, FBWF works on the file level.
When FBWF is enabled, all files and folders of a partition are protected unless included in an
exception list.
FBWF is disabled by factory default in the operating system image for SIMATIC IPC and
must be enabled and configured by the user.
When you enable FBWF, the write access to the C:\FBWF and D:\FBWF folders is enabled
by default.
Comparison between EWF and FBWF
● You should preferably use FBWF, as this allows a more flexible configuration and
immediate writing without rebooting.
● EWF is indispensable when HORM or compressed NTFS is used.
Configuring the FBWF
The FBWF can be configured in the command console using the program FBWFMGR.EXE.
Note
• Observe the following syntax: You must always append a space character to the colon
following the drive letter.
• You must restart the system to activate the changes for direct write access.
• Only existing files and folders can be included in the exception list.
Function
Display the current FBWF status
Enable FBWF after the next startup
Write to protected files
Adding/removing elements in the exception list:
•
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NOTICE
Activate only one write filter per partition - otherwise you risk data loss!
EWF and FBWF are preinstalled in the SIMATIC IPC images.
Ensure that only one write filter is enabled on a partition, otherwise you risk data loss!
Add file
Command
fbwfmgr /displayconfig
fbwfmgr /enable
fbwfmgr /commit c: \Test.txt
fbwfmgr /addexclusion C: \Test.txt
Operating Instructions, 12/2016, A5E03409486-AE
SIMATIC IPC277D