[sclug] rsync-like way of updating destination with newer files?

[Peter Grandi]

[ ... ]

> However I want, when I've altered or added files on the
> laptop, that I can automatically copy them back to the
> desktop.

Same situation here. Bu I use the laptop for everything, and the
desktop just for backup and file service.

> My first thought was rsync again, but this will
> restore older copies of files I've modified on the desktop
> since I last synced the two machines.

A very crude solution is adding "-u" to "rsync -axHS -v" for
example. It does not handle deletions well of course, but then
it is very difficult to do that.

> This is not what I want :-) I'd have thought it was a
> common-enough requirement [ ... ]

I have just been looking for this myself for work, so I an share
the results. There are many such tools and slightly different
approaches. There is a list on Wikipedia too which includes some
2-way ones:

  http://en.wikipedia.org/wiki/File_synchronization

I have seen 'csync' highly recommended, and I will try it. One
used by a colleague is 'unison'. Novell have done an interesting
one called 'iFolder' (apparently unfinished though).

  http://www.csync.org/
  http://www.cis.upenn.edu/~bcpierce/unison/
  http://www.novell.com/products/ifolder/

My current list also includes:

  cwrsync	<http://www.itefix.no/i2/node/10650>
  drsync	<http://hacks.dlux.hu/drsync/drsync.html>
  rsnapshot	<http://www.rsnapshot.org/>
  BackupPC	<http://backuppc.sourceforge.net/>
  fsbackup.pl	<http://www.opennet.ru/dev/fsbackup/index_eng.shtml>
  DirsSync	<http://dirssync.sourceforge.net/>
  GNOME Conduit	<http://www.conduit-project.org/>
  SyncDir	<http://syncdir.sourceforge.net/>
  FullSync	<http://fullsync.sourceforge.net/>
  DirSyncPro	<http://directorysync.sourceforge.net/>
  JFileSync	<http://jfilesync.sourceforge.net/>
  SynchronEX	<http://www.xellsoft.com/SynchronEX.html>
  PowerFolder	<http://wiki.powerfolder.com/wiki/Transfer_Modes>
  SuperFlexible	<http://www.superflexible.com/linux.htm>
  DeltaCopy	<http://www.aboutmyip.com/AboutMyXApp/DeltaCopy.jsp>

There are other approaches. Some people keep their home
directory entirely under a versions control system like
SVN and check in/check out updates across several machines.

Another is to use a "migrating" filesystem like OpenAFS or
Coda/Intermezzo (far more complicated).