A cluster of multiple Elasticsearch (ES) nodes can be configured by adapting the elasticsearch.yml file contained in the config directory of Elasticsearch.

Adapt and add the following configuration options to the file:

cluster.name: flowable-cluster  # name of the flowable cluster
node.name: node2  # name of the specific node within the cluster
node.master: true
node.data: true
discovery.zen.ping.unicast.hosts: node1  #list of hostnames/IPs of other nodes in the cluster

Please be aware that at least a cluster of three nodes is recommended for a productive setup.

Please also check the Elasticsearch cluster manual for further information.

In addition, modify the Flowable Server properties to add the Elasticsearch nodes for failover purposes: