Re: Partial transfer of rsyncrypto encrypted files

[Robin L. P. <rlp...@di...>]

On Thu, Jul 30, 2009 at 11:33:10PM +0200, Jan Alphenaar wrote:
> Hi,
> 
> I was recently playing around with rsyncrypto and rsync and found
> some interesting behavior during one of my large file transfers.
> 
> This is the situation. After encrypting my large file
> (approximately 1GB), rsync starts copying this file to my server.
> Here is the rsync command used, I modified it a bit to make it
> easier to read. Note, the "partial" option is used. In case the
> transfer is interrupted, rsync leaves the partially transferred
> file on the server.
> 
> rsync -rlt -v --partial -e ssh Test.zip jan@<servername>:/data
> 
> Half way down I interrupt the transfer, the partially transferred
> file stays on the server as expected. In the next session the file
> is again encrypted with rsyncrypto. Then I start a new rsync copy
> of the file, expecting rsync would continue with the partially
> transferred file, but it does not, it starts over at the
> beginning. Lets call this case a.

If you let it keep going for a while, does the apparent speed (use
"-P" instead of partial and it'll do partial and show you the
progress) speed up a whole great big bunch?  I expect that it will.

IIRC, the first few blocks in an rsyncrypto encrypted file are
always different, but the rest of the file is the same.

-Robin