In modern distributed systems, the ability to replicate data between separate environments is crucial for ensuring high availability, disaster recovery, and performance optimization. Couchbase’s XDCR (Cross Data Center Replication) feature allows seamless replication of data between clusters, enabling robust data sharing across geographically or logically isolated environments. This guide walks you through setting up XDCR between two Couchbase clusters hosted in separate Amazon EKS (Elastic Kubernetes Service) clusters within different VPCs. To follow this guide, ensure you have an AWS CLI installed and configured, an AWS account with permissions for creating VPCs, EKS clusters, and security groups, familiarity with Kubernetes and tools like kubectl and Helm, Helm installed to deploy Couchbase, basic knowledge of networking concepts, including CIDR blocks, routing tables, and DNS. The guide consists of seven steps: deploying EKS clusters in separate VPCs, peer the VPCs for inter-cluster communication, test connectivity by deploying NGINX in Cluster2, configuring DNS forwarding, deploying Couchbase, setting up XDCR, and finally, cleaning up resources. Through this guide, you’ll have a production-ready setup with the skills to replicate this in your environment.