[CentOS] clustering vs. xen

How does clustering relate to virtual hosts under xen?  Can you make a 2 
host failover cluster as the xen dom0 and have it take care of the 
guests or would you build 2 independent xen hosts and configure guests 
as failover clusters?  Or is there some other approach?

-- 
   Les Mikesell
    lesmikesell at gmail.com