Admin : please, can you dell this post.
I haven't solved the problem, but i have several ways to explore before reasking
I upgraded the MyBook with MyLenny Firmware,
then i followed instructions (http://www.dd-wrt.com/wiki/index.php/Rsync_Backup_Server) to install and setup rsync.
But the problem is that rsync daemon never start.
When i do a "ps", i have only bash and ps running, and not rsync daemon !
Can you help me ? Have you got an idea ?
I wasn't able to find someone on the net with the same problem !