Couchbase Server enhances data safety and performance by supporting cross datacenter replication (XDCR), which facilitates disaster recovery and improves data locality by replicating data between clusters. The text explains how to use Docker to create multiple Couchbase Server clusters with two nodes each, detailing the process of setting up these clusters and joining nodes via unique port mappings. The focus then shifts to configuring XDCR for bucket replication between clusters, emphasizing the need for replication to occur between clusters rather than nodes, and highlighting the importance of using container IPs instead of host IPs in this setup. The replication setup ensures that any changes made in one cluster are reflected in the remote cluster, thus enabling effective data synchronization and recovery strategies.