7.3. Enabling Gluster Block Storage as Backend for Metrics

Follow the tasks mentioned below to enable Gluster Block Storage as backend for metrics

Note

By default, since Container Native Storage performs three-way replication, data will be available to the restarted node from anywhere in the cluster. As a result, it is recommended that Cassandra-level replication is turned off to avoid capacity overhead
  1. To enable metrics in Openshift Container platform, see https://access.redhat.com/documentation/en-us/openshift_container_platform/3.10/html-single/configuring_clusters/#install-config-cluster-metrics
  2. The openshift_metrics_cassandra_storage_type ansible variable should be set to dynamic: 
    [OSEv3:vars]openshift_metrics_cassandra_storage_type=dynamic
    For example, a sample set of variables for openshift_metrics_ are listed below. 
    openshift_metrics_install_metrics=true
openshift_metrics_storage_kind=dynamic
openshift_metrics_hawkular_nodeselector={"node-role.kubernetes.io/infra": "true"}
openshift_metrics_cassandra_nodeselector={"node-role.kubernetes.io/infra": "true"}
openshift_metrics_heapster_nodeselector={"node-role.kubernetes.io/infra": "true"}
openshift_metrics_storage_volume_size=10Gi
openshift_metrics_cassandra_pvc_storage_class_name="glusterfs-registry-block"
  3. Run the Ansible playbook. For more information, see https://access.redhat.com/documentation/en-us/openshift_container_platform/3.10/html-single/configuring_clusters/#install-config-cluster-metrics.
  4. To verify, execute the following command: 
    # oc get pods --n openshift-infra
    It should list the following pods running: 
    heapster-cassandra
heapster-metrics
hawkular-&*9

Note

For more information regarding metrics storage considerations, see https://access.redhat.com/documentation/en-us/openshift_container_platform/3.10/html-single/configuring_clusters/#metrics-data-storage.