Ignore the answer on AD, as yours is about Domino. As for putting servers under an OU, that is fine. I generally create an OU just for servers, like /Servers/Domain Name so that I can put the wild card entry of */Servers/Domain Name into ACLs and the like for ease of administration. Each domain controller in an Active Directory forest can create a little bit less than 2.15 billion objects during its lifetime. Hope the is link will help http://technet.microsoft.com/en-us/library/cc756101(WS.10).aspx

Ignore the answer on AD, as yours is about Domino. As for putting servers under an OU, that is fine. I generally create an OU just for servers, like /Servers/Domain Name so that I can put the wild card entry of */Servers/Domain Name into ACLs and the like for ease of administration. Each domain controller in an Active Directory forest can create a little bit less than 2.15 billion objects during its lifetime. Hope the is link will help http://technet.microsoft.com/en-us/library/cc756101(WS.10).aspx