Perhaps permission problems...

The rsync options chosen are:
-g = preserve group
-o = preserve owner
-p = preserve permissions
-t = preserve modification times
-v = verbose (for the log)
-z = compress files during transfer
There is a similar example to your code: http://ksantema.wordpress.com/2009/1...een-aix-hosts/

Honestly.... unless you try to explain better how files are "doubled"... and use a little better english is hard have an idea of the problem.