On Fri, Apr 20, 2001 at 08:53:23AM -0400, Randy Kramer wrote:
...
> rsync -a -vv --progress --partial [--compare-dest=<subdirectory_name>] \
> carroll.cac.psu.edu::mandrake-iso/mandrakefreq-i586-20010316.iso \
> mandrakefreq-i586-20010316.iso
...
> In reading about the --compare-dest option, it sounded like I could keep
> two local copies of the file I wanted to update, one in the download
> directory and one in a subdirectory specified in the --compare-dest
> option. I hoped, that if I restarted rsync after an interruption, it
> would continue building the partially transferred file but use the file
> in the --compare-dest directory for comparison to the original and as
> "raw material" to avoid transferring duplicate blocks.
Note that if the target file ("mandrakefreq-i586-20010316.iso") is found
in the target directory ("."), it will take precedence over a file by
the same name in the compare-dest directory. Your compare-dest directory
should contain the old complete file but with the same name as the new one.
> It did not work for me, but it might have been because:
>
> -I did not set things up properly -- my hard disk does not have space
> for three copies of the iso, so I burned a CD-Rom and used it for the
> --compare-dest copy. If I had more hard disk space, I would try this
> again with the third copy in a subdirectory below the directory I am
> transferring the iso into.
The CD-ROM would have to have a file called mandrakefreq-i586-20010316.iso;
is that what it had, or did you burn the whole CD from the iso image?
> -The --compare-dest option only works for entire files -- if you are
> transferring multiple files, those that have been successfully
> transferred are recognized as completed by rsync and are not rechecked,
> those that have not been transferred use the files in --compare-dest as
> the raw material for the resumption of the rsync process.
Yes, files that have been successfully transferred and have a matching
timestamp will be skipped by rsync unless you're using -I to ignore
skipping files that have a matching timestamp, as the rsync man page
section on --compare-dest says.
- Dave Dykstra
