Traffic Splitting
editTraffic Splitting
editThe default Kubernetes service created by ECK, named <cluster_name>-es-http
, is configured to include all the Elasticsearch nodes in that cluster. This configuration is good to get started and is adequate for most use cases. However, if you are operating an Elasticsearch cluster with different node types and want control over which nodes handle which types of traffic, you should create additional Kubernetes services yourself.
As an alternative, you can use features provided by third-party software such as service meshes and ingress controllers to achieve more advanced traffic management configurations. Check the recipes directory in the ECK source repository for a few examples.
The service configurations shown in these sections are based on the following Elasticsearch cluster definition:
apiVersion: elasticsearch.k8s.elastic.co/v1 kind: Elasticsearch metadata: name: hulk spec: version: 8.15.2 nodeSets: # Dedicated master nodes - name: master count: 3 config: node.roles: ["master"] # Dedicated data nodes - name: data count: 6 config: node.roles: ["data"] # Dedicated ingest nodes - name: ingest count: 3 config: node.roles: ["ingest"] # Dedicated coordinating nodes - name: coordinating count: 3 config: node.roles: [] # Dedicated machine learning nodes - name: ml count: 3 config: node.roles: ["ml"] # Dedicated transform nodes - name: transform count: 3 config: node.roles: ["transform"]
Create services for exposing different node types
editThe following examples illustrate how to create services for accessing different types of Elasticsearch nodes. The procedure for exposing services publicly is the same as described in Allow public access.
apiVersion: v1 kind: Service metadata: name: hulk-es-coordinating-nodes spec: ports: - name: https port: 9200 targetPort: 9200 selector: elasticsearch.k8s.elastic.co/cluster-name: "hulk" elasticsearch.k8s.elastic.co/node-master: "false" elasticsearch.k8s.elastic.co/node-data: "false" elasticsearch.k8s.elastic.co/node-ingest: "false" elasticsearch.k8s.elastic.co/node-ml: "false" elasticsearch.k8s.elastic.co/node-transform: "false"
apiVersion: v1 kind: Service metadata: name: hulk-es-ingest-nodes spec: ports: - name: https port: 9200 targetPort: 9200 selector: elasticsearch.k8s.elastic.co/cluster-name: "hulk" elasticsearch.k8s.elastic.co/node-ingest: "true"
apiVersion: v1 kind: Service metadata: name: hulk-es-non-master-nodes spec: ports: - name: https port: 9200 targetPort: 9200 selector: elasticsearch.k8s.elastic.co/cluster-name: "hulk" elasticsearch.k8s.elastic.co/node-master: "false"
Specify a custom service in elasticsearchRef
editYou can then use your custom service in the elasticsearchRef
element when specifying connections between Elasticsearch and other stack applications. This is an example on how to target only coordinating node from Kibana:
apiVersion: kibana.k8s.elastic.co/v1 kind: Kibana metadata: name: hulk spec: version: 8.15.2 count: 1 elasticsearchRef: name: "hulk" serviceName: "hulk-es-coordinating-nodes"