Re: [Duplicity-talk] Duplicity crashes on locked files (windows)

[NwDsk]

> Paul Harris wrote:
> > It would certainly be a highlight if duplicity could
> > backup locked files (via shadow copy IIRC).
>
> Yes, its called Shadow Copy: http://en.wikipedia.org/wiki/Shadow_Copy
>
> However, I'm not familiar enough with Windows and Cygwin to know if
> shadow copy is available through Cygwin, and if so how to call it.
>
> Perhaps a volunteer could write some code.
>
> ...Thanks,
> ...Ken

No need to. It is already possible by first creating a
ShadowCopy and then have duplicity backing up that
ShadowCopy. For duplicity it is just a mapped drive and
there is no need for ShadowCopy interacting with Cygwin
or so.

The procedure is to run a batch file in which to create
a ShadowCopy of a (or more) volume(s). Since this ShadowCopy
is volatile it needs to call a second batch-file on the fly
in which the actual duplicity run takes place after a drive
letter has been mapped to the ShadowCopy.

Here you find a basic script to perform the essential part:
http://blogs.msdn.com/adioltean/archive/2005/01/05/346793.aspx
At the end one should replace the 'copy' part with your
duplicity command and just before that one should perform
the drive mapping with dosdev.exe:
http://blogs.msdn.com/adioltean/archive/2005/10/04/477164.aspx
When deploying on multiple systems one should add a small hack
to start the ShadowCopy service if it has not been started yet.

For my backups I use rsync and rdiff-backup a lot (only used
duplicity in test-setups) and I always proceed like this with 
ShadowCopies. Next to the possibility to backup open files
it also gives you a true point-in-time backup which often is
to be preferred over a sliding window backup.

Erwin