disconnected synchronization (mostly unidirectional)

Konrad Karl
Sat, 10 Mar 2007 19:43:31 -0000

Hi List,

please consider the following scenario:
(and pleast forgive if I have not googled enough but I was unsuccessful to
find an app what exactly does what I want)

machine A (office) is, where most file changes/downloads etc happen.
                   and it has limited internet access (only proxy possible)

Machine B (home) has low bandwidth, is NATed etc.

So I would like to use an USB hard drive as transportation medium.

First lets assume, A and B have been brought to sync somehow.

Afterwards I could do a disconnected rsync operation like follows:
(assuming transfer A -> B)

1.) get B's hard disk contents metadata  - perhaps the contents of
   rsync's file list can be stored onto the transportation medium.

2.) (in the office) let rsync generate its source file list from A
    but instead of connecting to B and get the destinations file
    list load B's list from the USB drive.

3.) store the files which needed to be transfered and all the
    other information (what has to be deleted, file attrs etc)
    onto a shadow directory on the USB drive.

4.) drive home :-)

5.) again using rsync, copy the files to their final destination
    and do all the other things required using the info stored
    on the USB drive.

6.) result: B should be equal to A

For a first approach it would be fine to not use the
"rsync" algorithm (transfer file differences only) because
implementing this will perhaps require considerable work and
hard drives are cheap nowadays.

What do you think?

Regards,
Konrad