anchor.diff:  volume] and be able to survive a pod being restarted or recreated. This is ideal
   if you require your metric data to be guarded from data loss.
   
  +For cluster metrics to work with persistent storage, ensure that the persistent volume has the *ReadWriteOnce* access mode. If not, the persistent volume claim will not be able to find the persistent volume, and Cassandra will fail to start.
  +
   To use persistent storage with the metric components, ensure that a
   link:../architecture/additional_concepts/storage.html#persistent-volumes[persistent
   volume] of sufficient size is available. The creation of
  
positive.code: By default, the OpenShift installer creates this template, and it can be found
  at the following path:
  
  ====
  ----
  /usr/share/ansible/openshift-ansible/roles/openshift_examples/files/examples/v1.1/infrastructure-templates/enterprise/metrics-deployer.yaml
  ----
  ====
  
  You will need to save your completed file with the file name *_metrics.yaml_*.
  
  ====
  [source,yaml,options="nowrap"]
  ----
  apiVersion: "v1"
  kind: "Template"
  metadata:
    name: metrics-deployer-template
    annotations:
      description: "Template for deploying the required Metrics integration. Requires cluster-admin 'metrics-deployer' service account and 'metrics-deployer' secret."
      tags: "infrastructure"
  labels:
    metrics-infra: deployer
    provider: openshift
    component: deployer
  objects:
  -
    apiVersion: v1
    kind: Pod
    metadata:
      generateName: metrics-deployer-
    spec:
      containers:
      - image: ${IMAGE_PREFIX}metrics-deployer:${IMAGE_VERSION}
        name: deployer
        volumeMounts:
        - name: secret
          mountPath: /secret
          readOnly: true
        - name: empty
          mountPath: /etc/deploy
        env:
          - name: PROJECT
            valueFrom:
              fieldRef:
                fieldPath: metadata.namespace
          - name: IMAGE_PREFIX
            value: ${IMAGE_PREFIX}
          - name: IMAGE_VERSION
            value: ${IMAGE_VERSION}
          - name: PUBLIC_MASTER_URL
            value: ${PUBLIC_MASTER_URL}
          - name: MASTER_URL
            value: ${MASTER_URL}
          - name: REDEPLOY
            value: ${REDEPLOY}
          - name: USE_PERSISTENT_STORAGE
            value: ${USE_PERSISTENT_STORAGE}
          - name: HAWKULAR_METRICS_HOSTNAME
            value: ${HAWKULAR_METRICS_HOSTNAME}
          - name: CASSANDRA_NODES
            value: ${CASSANDRA_NODES}
          - name: CASSANDRA_PV_SIZE
            value: ${CASSANDRA_PV_SIZE}
          - name: METRIC_DURATION
            value: ${METRIC_DURATION}
      dnsPolicy: ClusterFirst
      restartPolicy: Never
      serviceAccount: metrics-deployer
      volumes:
      - name: empty
        emptyDir: {}
      - name: secret
        secret:
          secretName: metrics-deployer
  parameters:
  -
    description: 'Specify prefix for metrics components; e.g. for "openshift/origin-metrics-deployer:v3.1", set prefix "openshift/origin-"'
    name: IMAGE_PREFIX
    value: "openshift/origin-"
  -
    description: 'Specify version for metrics components; e.g. for "openshift/origin-metrics-deployer:v3.1", set version "v1.1"'
    name: IMAGE_VERSION
    value: "latest"
  -
    description: "Internal URL for the master, for authentication retrieval"
    name: MASTER_URL
    value: "https://kubernetes.default.svc:443"
  -
    description: "External hostname where clients will reach Hawkular Metrics"
    name: HAWKULAR_METRICS_HOSTNAME
    required: true
  -
    description: "If set to true the deployer will try and delete all the existing components before trying to redeploy."
    name: REDEPLOY
    value: "false"
  -
    description: "Set to true for persistent storage, set to false to use non persistent storage"
    name: USE_PERSISTENT_STORAGE
    value: "true"
  -
    description: "The number of Cassandra Nodes to deploy for the initial cluster"
    name: CASSANDRA_NODES
    value: "1"
  -
    description: "The persistent volume size for each of the Cassandra nodes"
    name: CASSANDRA_PV_SIZE
    value: "10Gi"
  -
    description: "How many days metrics should be stored for."
    name: METRIC_DURATION
    value: "7"
  ----
  ====
  
  [[deployer-template-parameters]]
  ==== Deployer Template Parameters
  
negative.code: For instance, if you have a custom install in which the Kubernetes master is not
  available under `https://kubernetes.default.svc:443` you can specify the value
  to use instead with the `*HAWKULAR_METRICS_HOSTNAME*` parameter. If you wish to
  deploy a specific version of the metrics components, you can do so with the `*IMAGE_VERSION*` parameter.
  
  == Deploying the Metric Components
  
  