With Novell's move to Linux, our site will probably move to MS Active directory. We are a small school district with two buildings connected by 100m of fiber. We are considering two directory structures. 1. Single domain, two DCs one at the elementary and one in the secondary. 2. Two domains, one in elementary and one at secondary. What are the advantages/disadvantages of these two? As I understand it, plan 1 provides redundency if one server goes down, but creates more WAN traffic for replication. Plan 2 has less WAN traffic, but if one server goes down, that domain is down. Looking for recommendations.