Multiple zones and single controller

Would be possible, with One, to create a cloud across multiple datacenter and manage each install from a single sunstone ?

in example, I would like to unify 3 datacenters, allowing users to create instances in all datacenters or scale up an app across multiple DCs.

Should I place a controller on each DC or a single controller is able to manage everything ?

Is this possible? Any link to proper docs?

This may fit your use case