IP Failover + Open Directory = The BIG picture?

Howdy! I have been working with Tiger server for awhile and have been curious about IP failover. I have read the Apple docs and many of the posts here, but I am wondering about the "big" picture.... I have two servers - both 10.4.7 One of them is running various services including AFP, Web, Mail and OD. I unfortunately at this time do not have shareed storage such as a RAID or SAN. My main goal is to have the second server be idle and have them sync data during the night. There is not a lot of data to sync and it does not change that often. When the main server goes down I want the second to pick up all the services. So, this is what I believe I understand at this point: •Make sure configs are the same on both machines. I could do this by configing the main server and copying the prefs out of server admin and dropping them onto the backup's server admin. •Each have their own IP address and host names. •All services remain off on the backup server until IP failover turns them on. •The IP failover setup takes care of the rest by changing the host name and ip address info of the backup server when the main server goes down and then changes it back when the main server comes back up. Am I understanding this correctly? The most confusing part for me is what to do with OD. Do I run that service as a replica on the backup server or do I sync some directory manually with rsync or something similar? Any input would be greatly appreciated. Thanks![b]