cron'ing rsync over ssh

My setup is: I run rsync daemonized on various server machines in my LAN - i.e., the source machines certain partitions of which I want to backup. I would like the client, the destination archiving machine, to run hourly crons over ssh, but so far the only thing I have been able to do is rsync across (as root so that I am not denied anything) only after interactively supplying my root password to the ssh daemon. How do I get around interactive ssh interactive password requirement so that I can cron all these rsync client requests regularly?

I know passwordless implementation involve ssh-keygen and ssh-agent, but I haven't figured out what the proper usages are yet.

Thanks

-- 

Jesse Burkhardt
jesse@skybuilders.com  (w) 617-876-5680
goose@aerogoose.com    (h) 617-354-5523
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