XDCR replications are configured on a per-bucket basis.
Configure the replications from the XDCR tab of the Couchbase Web Console. As replication is on a per bucket basis, you must configure replication for each bucket to each target cluster.
Before configuring XDCR:
Configure all nodes within each cluster to communicate from the source cluster over the network to all nodes on the destination cluster.
Ensure that all Couchbase Server versions and platforms match. For instance, if you want to replicate from a Linux-based cluster, you need to do so with another Linux-based cluster.
Confirm that your cluster is properly sized and is able to handle new XDCR streams. For example, XDCR needs 1-2 additional CPU cores per stream and in some cases it will require more RAM and network resources as well. If a cluster is not properly sized for the existing workload plus the new XDCR streams, XDCR can compete for server resources and have a negative impact on overall performances.
Couchbase Server uses TCP/IP port
8091to exchange cluster configuration information. If you are communicating with a destination cluster over a dedicated connection or the Internet, you should ensure that all the nodes in the destination and source clusters can communicate with each other over ports
Under the XDCR tab, you can configure Remote Clusters for XDCR; these are named destination clusters you can select when you configure replication. When you configure XDCR, the destination cluster reference should point to the IP address of one of the nodes in the destination cluster. Once it has the connection with that one node, similar to how a Couchbase SDK does, it will receive the cluster topology of that destination cluster.
Ongoing Replications are the ones that are configured and operating currently. You can monitor the current configuration, current status, and the last time a replication process was triggered for each configured replication.