On the Setup Options page in the Active Directory Lightweight Directory Services Setup Wizard, you choose whether to install a unique Active Directory Lightweight Directory Services (AD LDS) instance or join an existing configuration set.

Setup option Result

A unique instance

If you choose to install a unique AD LDS instance, the AD LDS instance that you install will not be a part of any existing configuration set, and it will not have any replication partners. The wizard will create new, default copies of the configuration and schema directory partitions for the new AD LDS instance that you are creating. Any schema extensions that you have added to any other AD LDS instance will not be available in this new AD LDS instance.

A replica of an existing instance

If you choose to install a replica of an existing AD LDS instance, the AD LDS instance that you are installing will contain replicated copies of the configuration and schema directory partitions (including any schema extensions) from the instance from which you choose to replicate. In addition, you have an opportunity in the wizard to selectively replicate any application directory partitions that exist in the source configuration set. You must specify a running AD LDS instance as the source from which to replicate. To speed up the replication process for the new instance, you can use a restored copy of a previously backed-up AD LDS instance as the data source.

An AD LDS instance consists of a single copy of the AD LDS directory service, along with its associated directory store, assigned Lightweight Directory Access Protocol (LDAP) and Secure Sockets Layer (SSL) ports, and application event log. You can run multiple AD LDS instances simultaneously on a single computer.

You can join an AD LDS instance to a configuration set only during AD LDS installation.

Additional references