| ## Replicated Databases The registry database can be replicated within its cell. Each instance of a security server in a cell maintains a working copy of the database. Throughout this guide, the combination of a security server and its data (the registry database) is referred to as a replica. Typically, you create several replicas in a cell to enhance performance and reliability. The task of keeping the cell's replicas consistent is handled automatically by the security servers. Any changes that you make are automatically reflected in all replicas, as described in the following topic. ##