Backing up sparse files ... VM's and TrueCrypt ... etc

[blu-Z8efaSeK1ezqlBn2x/YWAg at public.gmane.org (Edward Ned Harvey)]

> > I haven't found anything satisfactory yet.
> 
> I noticed you didn't mention tar. I'd be surprised if it didn't
> understand sparse files. Though I don't know about the versions ported
> to Windows. And it wouldn't be able to provide incremental updates for
> changes within the sparse file.

Tar does support backing up and restoring sparse files.  However, it can't
do block-level incrementals of them.  The same is true for NTBackup.

For whatever reason, tar performance is horrible in cygwin windows, so in
windows, I'm currently using ntbackup to backup these files, and on OSX I
use tar.  Problem is ... it takes so long to send the whole file, I'll only
back up once a month or so.


> > I've also tried rsync.  People all over the place say it should do
> well, but
> 
> How about describing how you are using it? Assuming you are backing up
> to a network drive, which machine is it running on, and how is the data
> being transported over the network? What command line are you using?

It's been a while, I would have to repeat it now in order to remember how it
was done.  I'll do it, if there's any good reason to believe it'll help ...

Do you successfully, frequently, efficiently, backup sparse files via rsync,
including incrementals?