Running Metricbeat on Kubernetes

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You can use Metricbeat Docker images on Kubernetes to retrieve cluster metrics.

Kubernetes deploy manifests

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You deploy Metricbeat in two different ways at the same time:

  • As a DaemonSet to ensure that there’s a running instance on each node of the cluster. These instances are used to retrieve most metrics from the host, such as system metrics, Docker stats, and metrics from all the services running on top of Kubernetes.
  • As a single Metricbeat instance created using a Deployment. This instance is used to retrieve metrics that are unique for the whole cluster, such as Kubernetes events or kube-state-metrics.

Everything is deployed under the kube-system namespace by default. To change the namespace, modify the manifest file.

To download the manifest file, run:

curl -L -O https://raw.githubusercontent.com/elastic/beats/7.6/deploy/kubernetes/metricbeat-kubernetes.yaml

If you are using Kubernetes 1.7 or earlier: Metricbeat uses a hostPath volume to persist internal data. It’s located under /var/lib/metricbeat-data. The manifest uses folder autocreation (DirectoryOrCreate), which was introduced in Kubernetes 1.8. You need to remove type: DirectoryOrCreate from the manifest and create the host folder yourself.

Settings

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By default, Metricbeat sends events to an existing Elasticsearch deployment, if present. To specify a different destination, change the following parameters in the manifest file:

- name: ELASTICSEARCH_HOST
  value: elasticsearch
- name: ELASTICSEARCH_PORT
  value: "9200"
- name: ELASTICSEARCH_USERNAME
  value: elastic
- name: ELASTICSEARCH_PASSWORD
  value: changeme
Red Hat OpenShift configuration
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If you are using Red Hat OpenShift, you need to specify additional settings in the manifest file and enable the container to run as privileged.

  1. In the manifest file, edit the metricbeat-daemonset-modules ConfigMap, and specify the following settings under kubernetes.yml in the data section:

      kubernetes.yml: |-
        - module: kubernetes
          metricsets:
            - node
            - system
            - pod
            - container
            - volume
          period: 10s
          host: ${NODE_NAME}
          hosts: ["https://${HOSTNAME}:10250"]
          bearer_token_file: /var/run/secrets/kubernetes.io/serviceaccount/token
          ssl.certificate_authorities:
            - /var/run/secrets/kubernetes.io/serviceaccount/service-ca.crt
  2. Under the metricbeat ClusterRole, add the following resources:

      - nodes/metrics
      - nodes/stats
  3. Grant the metricbeat service account access to the privileged SCC:

    oc adm policy add-scc-to-user privileged system:serviceaccount:kube-system:metricbeat

    This command enables the container to be privileged as an administrator for OpenShift.

  4. Override the default node selector for the kube-system namespace (or your custom namespace) to allow for scheduling on any node:

    oc patch namespace kube-system -p \
    '{"metadata": {"annotations": {"openshift.io/node-selector": ""}}}'

    This command sets the node selector for the project to an empty string. If you don’t run this command, the default node selector will skip master nodes.

Deploy

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Metricbeat gets some metrics from kube-state-metrics. If kube-state-metrics is not already running, deploy it now (see the Kubernetes deployment docs).

To deploy Metricbeat to Kubernetes, run:

kubectl create -f metricbeat-kubernetes.yaml

To check the status, run:

$ kubectl --namespace=kube-system  get ds/metricbeat

NAME       DESIRED   CURRENT   READY     UP-TO-DATE   AVAILABLE   NODE-SELECTOR   AGE
metricbeat   32        32        0         32           0           <none>          1m

$ kubectl --namespace=kube-system  get deploy/metricbeat

NAME                    DESIRED   CURRENT   UP-TO-DATE   AVAILABLE   AGE
metricbeat                1         1         1            1           1m

Metrics should start flowing to Elasticsearch.