Fail-over Server

[Ryan Golhar]

I'm in the process of setting up a server to act as a failover server if
the primary server goes down.  The services I need to have failed over
include:

1. DHCP (maintaining current leases)
2. NIS 
3. NFS (user home directories)
4. License Server (FlexLM)

Can anyone recommend a way on how to handle this?  It would be easier
knowing other people's experiences with this.  Thanks,

Ryan