[rdiff-backup-users] windows profiles and refreshed files

[Patrick J. Walsh]

    I've just set up rdiff-backup to backup samba shares to a dedicated
failover machine.  I'm thrilled.  Our shares get backed up hourly now.  But
I have a question about updated but unchanged files.

    We use roaming profiles for our windows users so that they can log in
from different machines and see their familiar list of recent files, desktop
settings, etc.  Every time a user logs on, their profile is copied to the
local machine.  When they log off, it gets copied back.  Typically, very
little has changed.  But of course the time stamps are updated.

    My question is this: would there be any benefit to using the
--no-compare-inode option?  Would this decrease the number and size of files
generated?  Is there any penalty such as a speed decrease when using this
option?

    Or -- is there a way to tell rdiff to ignore changed file times if the
file is unchanged? 

    And finally -- does backing up a dir structure that has updated
modification times unnecessarily tax the server?  Should I then maybe
exclude these directories during the hourly updates and just back them up
once a day?

    Any feedback would be appreciated.

..Patrick

PS - I managed to get rdiff-backup going through an unencrypted link between
two computers with a private network connection using inetd and nc.  Works
great.  In case anyone has a secure link and feels that ssh just adds
overhead, I'd be happy to share the details of the setup.