Directory Proxy Server is designed to support high availability directory deployments. The proxy provides automatic load balancing as well as automatic failover and fail back among a set of replicated Directory Servers. Should one or more Directory Servers in the topology become unavailable, the load is proportionally redistributed among the remaining servers.
Directory Proxy Server actively monitors the Directory Servers to ensure that the servers are still online. The proxy also examines the status of each operation that is performed. Servers might not all be equivalent in throughput and performance. If a primary server becomes unavailable, traffic that is temporarily redirected to a secondary server is directed back to the primary server as soon as the primary server becomes available.
Note that when data is distributed, multiple disconnected replication topologies must be managed, which makes administration more complex. In addition, Directory Proxy Server relies heavily on the proxy authorization control to manage user authorization. A specific administrative user must be created on each Directory Server that is involved in the distribution. These administrative users must be granted proxy access control rights.