[BBLISA] Backing up sparse files ... VM's and TrueCrypt ... etc

[Edward Ned Harvey]

> Edward Ned Harvey wrote:
> > Crashplan does backup this way, but you can't restore a sparse file
> > sparsely from a crashplan backup.
> 
> Restores are rare, right? So it should not be terribly inconvenient to
> use a workaround, such as the technique for restoring sparseness to
> gzipped files (by piping to "cp --sparse=always"):

I didn't know you could do that.  In fact, I just tested this with a couple
small files (200M) and it worked perfectly.  Yes, it would be inconvenient
if you had to restore this way, but yes, it would be possible.  And that's
good news.  Thanks for that suggestion.

One caveat to beware though:  You would need the empty space on your HD to
be at least the sum of the apparent sparse volume size, plus the used size
within the sparse volume.  Because you'd first need to restore the un-sparse
file, and then while you copy it, it would consume again, all the nonzero
space inside the volume, before you could rm the un-sparse file.