Desktop mode and Service mode
Jul 18, 2016
Bvckup 2 can be run in one of two principal modes.
In desktop mode, which is the default, program's user interface and its backup engine share the same process, so you see a single instance of bvckup2.exe on your Task Manager list. Exiting the program stops both the engine and the UI, meaning that you need to be logged into Windows *and* to be running the program for the backups to run.
In service mode, the program splits the engine and user interface into two separate processes. The backup engine is installed as a Windows system service and it in the background, at all times. The user interface continues to run as a regular desktop program and it can be started and stopped at will. In this mode, logging out of Windows closes the user interface, but leaved the engine running, so Bvckup2 continues to make backups even if no one is logged in.
Compatibility with (legacy) Personal licenses
Under Personal licenses the program may be used in service mode, but doing so voids all access to the tech support.
This was one of 3 differences between two legacy license types - no tech support for running in the service mode. The other two - no support for running on Windows Servers and, the main one, the unconditional restriction for any work-related use.
If you are on a Personal license and require support for using the program in service mode, you will need to upgrade to the new Pro license. See Menu > Help > "Upgrade to Pro" for details.
Jul 18, 2016
Service mode caveats
Keep in mind that in a service mode the engine part runs under a different user account and as such it will not generally have the access to any shares that might be accessible to the (desktop) user account.
It will also most certainly will not have the access to any of the user's mapped network drives as these are a per-account property.
First, if you are backing up to- or from a remote share, you *must* use explicit network paths, such as \\server\share\path...
Second, if said remote share requires authentication, then you have two options:
⦁ Configure share access credentials in Bvckup 2 itself
⦁ Create a separate user account for the "bvckup2" service.
Switch service to run under this account, using Service Manager.
Add this new account to the Backup Operators group.
Grant this account required access rights on the share end.
The benefit of the second option is that the share access password is not getting stored in Bvckup 2 configuration, so it provides for a better security if one is required.
Jul 18, 2016
Switching the mode
1. Menu > Options > Preferences, check "Show 'Switch mode' option"
2. Menu > Options > Switch mode
You can tell Bvckup 2 to open a log window that shows the switching process by holding Ctrl button down when clicking on Apply in the "Switch mode" window.
The same log is also always written into the following file:
Jul 18, 2016
Switching the mode from command-line
As of Release 76 it's also possible to switch the mode from command line using the following command:
bvckup2.exe --set-mode <service|desktop> <config-path>
whereby <config-path> points at app's configuration directory in desktop mode. On Vista+ it will be:
The app must NOT be running when the switch is made to the service mode. To ensure this you can shut down the app from the command line using "terminate" command. See the following topic for details - https://bvckup2.com/support/forum/topic/411
Several additional parameters are supported by --set-mode command:
--console - opens the log console
--log <file> - redirects the log into <file>
--force - forces skipping over certain errors
--atomically - limits the switch to atomic NTFS move only
Also, when switching to the service mode:
--service-only - installs bvckup2 service, but skips the config move
which is meant for switching newly installed app instances that haven't been run yet.
The result of the switch is indicated with a process exit code. 0 is for OK, non-zero is for failure. Exact failure codes are TBD, please get in touch if you need help interpreting them.
Jul 18, 2016
What happens during the switch
Switching to the service mode does the following:
⦁ Creates %ProgramData%\Bvckup2 folder.
⦁ Moves or copies %ConfigPath%\engine to %ProgramData%\Bvckup2
⦁ Copies %ConfigPath%\bvckup2-service.log to
⦁ Creates bvckup2 service entry
⦁ Starts the bvckup2 service
Switching to the desktop mode does the following:
⦁ Stops the bvckup2 service
⦁ Moves or copies %ProgramData%\Bvckup2\engine to %ConfigPath%
⦁ Resets security information on %ConfigPath%\engine, recursively
⦁ Copies %ProgramData%\Bvckup2\bvckup2.log to
⦁ Removes bvckup2 service
%ConfigPath% here is the parameter from the command line.
May 11, 2020
When moving the engine folder, the program first attempts to move it using transactional NTFS rename operation. If it fails, it tries moving the folder with a conventional move operation. If this too fails, the mode switch will be aborted.
Earlier versions of the program fell back to _copying_ the folder, but this behavior was deprecated. This was done because the file block-hashes generated by delta copying are stored in the engine folder and these may grow to a substantial total size. Silently falling back to the copying caused the switch to suddenly take minutes instead of seconds and this led to all sorts of usability problems.
That is, mode switching expects to be able to _move_ the engine folder.
This means that the mode cannot be switched if the interactive user profile and %ProgramData% folder are located on different volumes. The workaround for this case is as follows:
1. Shut down the program.
2. Move (by copying) %LocalAppData%\Bvckup2 folder to a temporary place on the %ProgramData%'s volume. Say, it's Q:\Temp\Bvckup2.
3. Start the program from the command line with "-c Q:\Temp\Bvckup2" option.
4. Perform the mode switch, which will now go through.
5. Shut down the program (this will now exit just the UI).
6. Move (by copying) Q:\Temp\Bvckup2 back into %LocalAppData%
7. Start the program as usual
May 11, 2020
When creating/moving/copying folders - if there's an existing copy of the folder already in place, the app will try moving it out of the way by renaming into "%FolderName%_xxx (backup)", whereby xxx is current timestamp in NTFS time units.
The configuration folder move can be disabled altogether with --service-only parameter.
Finally, when some part of the switch sequence fails, the app undoes all changes already made and reports a failure.
Topic is locked.