Couchbase Server 4.5 Beta introduces a new full text search (FTS) service that enhances scalability, indexing speed, and security features such as authentication and audit logging. The FTS service, which remains a developer preview, allows for distributed search across multiple nodes, enabling efficient indexing and searching of text within Couchbase documents without third-party tools. The system uses a distributed architecture similar to data buckets, dividing full text indexes into fragments called pindexes that are spread across nodes. This design supports replication to speed up failover and ensures that search continues even during node failures, albeit with potential partial results if replicas aren't available. Users are encouraged to test the new functionality and provide feedback as the FTS team continues to refine the feature.