2.7. Moving the monitoring solution

Procedure

1. Save the following ConfigMap definition as the cluster-monitoring-configmap.yaml file:

   apiVersion: v1
   kind: ConfigMap
   metadata:
     name: cluster-monitoring-config
     namespace: openshift-monitoring
   data:
     config.yaml: |+
       alertmanagerMain:
         nodeSelector:
           node-role.kubernetes.io/infra: ""
       prometheusK8s:
         nodeSelector:
           node-role.kubernetes.io/infra: ""
       prometheusOperator:
         nodeSelector:
           node-role.kubernetes.io/infra: ""
       grafana:
         nodeSelector:
           node-role.kubernetes.io/infra: ""
       k8sPrometheusAdapter:
         nodeSelector:
           node-role.kubernetes.io/infra: ""
       kubeStateMetrics:
         nodeSelector:
           node-role.kubernetes.io/infra: ""
       telemeterClient:
         nodeSelector:
           node-role.kubernetes.io/infra: ""
       openshiftStateMetrics:
         nodeSelector:
           node-role.kubernetes.io/infra: ""
       thanosQuerier:
         nodeSelector:
           node-role.kubernetes.io/infra: ""

   Running this config map forces the components of the monitoring stack to redeploy to infrastructure nodes.

2. Apply the new config map:

   $ oc create -f cluster-monitoring-configmap.yaml

3. Watch the monitoring pods move to the new machines:

   $ watch 'oc get pod -n openshift-monitoring -o wide'

4. If a component has not moved to the infra node, delete the pod with this component:

   $ oc delete pod -n openshift-monitoring <pod>

   The component from the deleted pod is re-created on the infra node.