A-1-2 File-Based Write Filter - Omron NY Series Operating Manual

Command
ewfmgr c: -commitanddisable -
live
ewfmgr c: -disable
ewfmgr /h
Considerations
• EWF and FBWF cannot be used simultaneously.
• To prevent data loss in the event of a power failure, the use of a UPS is recommended.
• When the EWF function is enabled and a large amount of data is written, the system memory space
will be reduced and operation may become unstable. To prevent this problem, it is recommended
that a large amount of data be written to a different location.
• Automatic Adjustment of daylight saving time (DST) is incompatible with the Enhanced Write Filter
(EWF).
Additional Information
Refer to the Microsoft Developer Network (MSDN) for DST details.
A-1-2
File-Based Write Filter
The File-Based Write Filter (FBWF) is applicable to IPCs with a Windows 7 operating system.
The File-Based Write Filter (FBWF) intercepts file changes and stores them into a memory overlay in
RAM memory instead of applying them to the original volume.
When FBWF is enabled, all files and folders of a partition are protected unless they are included in an
exception list.
Additional Information
• Enhanced Write Filter (EWF) provides a similar function, but operates at the sector level,
while FBWF operates at the file level. FBWF is more flexible in its configuration than EWF
and allows immediate writing without rebooting.
• Refer to the Microsoft Developer Network (MSDN) for detailed information.
Application
EWF and FBWF provide the following benefits:
• Write-protect one or more partitions on a system.
• Make it possible to revert changes and revert to the original disk content.
• Enable booting from read-only media.
By redirecting all write requests to RAM, EWF and FBWF enable the run-time image to maintain the
appearance of a writable run-time image.
• Improve the file system performance when using relatively slow storage.
NY-series Industrial PC Operating Systems and Software Utilities Manual (W616)
Function
Writes all the changes in the mem-
ory overlay to the physical disk im-
mediately, and disables the disk
protection.
Disables the disk protection.
Displays a helpscreen that explains
all commands and options availa-
ble.
Appendices
Remarks
Protection is also disabled immedi-
ately. No restart is required.
The protection is not disabled until
the system is restarted.
A complete reference can also be
found at the Microsoft Developer
Network (MSDN).
A
A-3