Apart from being assigned a degraded status, a directory server can change status if an administrator performs one of the following tasks on the topology:
Full update. When a replicated domain is initialized online from another server in the topology, the directory server status for that domain changes to FULL_UPDATE_STATUS. When the full update has completed, the directory server reinitializes its connection to the topology, and the status is reset to NORMAL_STATUS.
Local import or restore. When a replicated domain is reinitialized by using a local import or restore procedure, the directory server status for that domain changes to NOT_CONNECTED_STATUS.
Resetting the generation ID. If a replicated domain connects to a replication server with a generation ID that is different from its own, the domain is assigned a BAD_GEN_ID status. A domain can also be assigned this status if a reconnection occurs after a full online update, a local import, or a restore with a set of data that has a different generation ID to that of the replication server.
In addition, you might need to reset the generation ID of all the replication servers in the topology by running the reset generation ID task on the directory server. This causes all the replication servers in the topology to have a different ID to the ID of the directory servers to which they are connected. In this case, the directory servers are assigned a BAD_GEN_ID status.