http://msmvps.com/blogs/ulfbsimonweidner/archive/2008/07/31/how-many-infrastructure-masters-do-you-have.aspxThere are certain roles in Active Directory - which is a multi-master directory (meaning that every DC can write if he's member of the domain) - which need a "single-master", someone who takes care that certain things are only performedenCommunityServer 2008.5 SP2 (Build: 40407.4157)