I did a Disater Recover session at the 2010 FileMaker Devcon. The session ID was "COR002_backup_DR", you may be able to pick up the conference materials from FMI.
- backup strategies for Windows and OSX
- config settings for FileMaker Server that will assist in DR
- DR procedures and testing (procuedure for quick installation, restore from backup,...)
- automated & safe ways to close FM hosted files
- failover setup