does partial option work over ssh?

[Glen Davison]

On Fri, 2006-07-14 at 10:34 +0200, Paul Slootman wrote:
> On Fri 14 Jul 2006, Glen Davison wrote:
> > 
> > This is what I believe SHOULD work, but it doesn't:
> > 
> > rsync -aP -e 'ssh -c blowfish' user at host:/path/to/file1/ newpath/
> > 
> > - it just starts again.
> 
> The interrupted rsync session also needs to have had the --partial
> option (implied here by -P) active, otherwise the interrupted session
> will have discarded the partial data.

Yes, it did have it, and there was a file (file1) left there.  But a new
session starts creating a new file: '.file1.gibberish'

The man page is not very clear; I was expecting this new file to either
begin as a copy of the partial file1 and grow from there, or to consist
entirely of data to append.  In my most recent attempt, the new file
began smaller than file1 (probably at size 0, but I missed that) and has
now grown to greater than the difference between the partial file1 and
the original/source, which suggests to me that it is simply a whole new
copy.

[written later] The copy did succeed.  It appears that while it was
checking the blocks in the previous partial, it built up the new copy
gradually, which I did not expect.  Does it checksum each block, then
copy that block to the temp file from the partial?

> If --partial _was_ in effect, then how did you determine it starts
> again? Remember that rsync will still verify the contents of the partial
> transfer, i.e. use checksums to verify the data already there. That may
> look like it's transferring again.  If you want to skip that, use
> --append to just append data.

I am now trying this, and it does seem to get onto the copying a bit
quicker.  (I had to upgrade the sending end to get --append.  2.6.3
didn't have it)  But at a price - for some reason the session/
connection seems to be quite flaky now; either "connection unexpectedly
closed" or hanging.

> > Both machines are behind firewalls, but going in the above direction
> > should be okay; plus of course it does succeed in copying, just not in
> > appending.
> > 
> > A colleague here says he has tried to do the same thing, and he could
> > get it to work for an rsync daemon, but not over ssh.
> 
> The underlying transport is not relevant.
> 
> Paul Slootman

Thanks for your response Paul.  It did help.  :)

Glen

-- 
Glen Davison            davo at sirca.org.au
SIRCA Pty Ltd           Ph 9236 9133