OpenDJ uses advanced data replication with automated conflict resolution to help ensure your directory services remain available in the event a server crashes or a network goes down, and also as you backup or upgrade your directory service. You can configure data replication as part of OpenDJ installation, and in many cases let replication do its work in the background. For some deployments you may choose not to accept the default replication configuration. This chapter shows how to configure replication with command-line tools, and covers other topics related to replicated directory environments.