EWFMgrCommit question

[Dick Dawson]

I will be implementing an audio encoding application on blade computers with
removable CF module so my understanding is that I can only use EWF Ram-Reg
mode. I expect that I will have an occasional need to update one DLL on the
system. It appears to me that EwfMgrCommitFile is too restrictive for this
purpose so I will need to use EwfMgrCommit. The documentation for this
function says "The overlay data is committed on the next restart."

The blade computers are headless and diskless and are expected to run
continuously. The only restart might be because of a crash or power
failure, or perhaps some maintenance operation. In any case they do not
have keyboard, etc. needed to control an orderly shutdown. In the event of
a "disorderly shutdown" such as pressing a reset button or crash, will the
overlay data be committed?

 

[Adora Belle Dearheart]

I will be implementing an audio encoding application on blade computers with
removable CF module so my understanding is that I can only use EWF Ram-Reg
mode. I expect that I will have an occasional need to update one DLL on the
system. It appears to me that EwfMgrCommitFile is too restrictive for this
purpose so I will need to use EwfMgrCommit. The documentation for this
function says "The overlay data is committed on the next restart."

The blade computers are headless and diskless and are expected to run
continuously. The only restart might be because of a crash or power
failure, or perhaps some maintenance operation. In any case they do not
have keyboard, etc. needed to control an orderly shutdown. In the event of
a "disorderly shutdown" such as pressing a reset button or crash, will the
overlay data be committed?

No, it won't be. I believe there's an option for committing without a
restart, though.

 

[KM]

Dick,

With EWF RAM Reg the overlay is going to be committed on graceful shutdown. In case of sudden powerdown the overlay will not be
committed.

Unless you expectedly using it with "-live" switch of ewfmgr (there is also API for that). But then EWF is disabled and to enable it
again you will have to reboot the system.

This is all limitations of current implementation of EWF.


I wonder how you update the DLL on the headless device? If it is an admin mode (where you connect a keybd to the device) you can
safely commit the overlay and reboot the device. If the update is happening over network (what's running on the client side? DUA,
SMS, etc?) then you don't really need to make the DLL persistent right away. Rather always replace it in the overlay (just copy
over) and issue a commit (will be down on shutdown). If next shutdown is graceful - it will commit the change, if not - you will
lose it and go back to old version of the DLL but the system will still be useable.