6.2. Removing monitoring stack from OpenShift Data Foundation

Procedure

1. List the pods and PVCs that are currently running in the openshift-monitoring namespace.

   $ oc get pod,pvc -n openshift-monitoring

   Example output:

   NAME                           READY   STATUS    RESTARTS   AGE
   pod/alertmanager-main-0         3/3     Running   0          8d
   pod/alertmanager-main-1         3/3     Running   0          8d
   pod/alertmanager-main-2         3/3     Running   0          8d
   pod/cluster-monitoring-
   operator-84457656d-pkrxm        1/1     Running   0          8d
   pod/grafana-79ccf6689f-2ll28    2/2     Running   0          8d
   pod/kube-state-metrics-
   7d86fb966-rvd9w                 3/3     Running   0          8d
   pod/node-exporter-25894         2/2     Running   0          8d
   pod/node-exporter-4dsd7         2/2     Running   0          8d
   pod/node-exporter-6p4zc         2/2     Running   0          8d
   pod/node-exporter-jbjvg         2/2     Running   0          8d
   pod/node-exporter-jj4t5         2/2     Running   0          6d18h
   pod/node-exporter-k856s         2/2     Running   0          6d18h
   pod/node-exporter-rf8gn         2/2     Running   0          8d
   pod/node-exporter-rmb5m         2/2     Running   0          6d18h
   pod/node-exporter-zj7kx         2/2     Running   0          8d
   pod/openshift-state-metrics-
   59dbd4f654-4clng                3/3     Running   0          8d
   pod/prometheus-adapter-
   5df5865596-k8dzn                1/1     Running   0          7d23h
   pod/prometheus-adapter-
   5df5865596-n2gj9                1/1     Running   0          7d23h
   pod/prometheus-k8s-0            6/6     Running   1          8d
   pod/prometheus-k8s-1            6/6     Running   1          8d
   pod/prometheus-operator-
   55cfb858c9-c4zd9                1/1     Running   0          6d21h
   pod/telemeter-client-
   78fc8fc97d-2rgfp                3/3     Running   0          8d
   
   NAME                                                              STATUS   VOLUME                                     CAPACITY   ACCESS MODES   STORAGECLASS                  AGE
   persistentvolumeclaim/my-alertmanager-claim-alertmanager-main-0   Bound    pvc-0d519c4f-15a5-11ea-baa0-026d231574aa   40Gi       RWO            ocs-storagecluster-ceph-rbd   8d
   persistentvolumeclaim/my-alertmanager-claim-alertmanager-main-1   Bound    pvc-0d5a9825-15a5-11ea-baa0-026d231574aa   40Gi       RWO            ocs-storagecluster-ceph-rbd   8d
   persistentvolumeclaim/my-alertmanager-claim-alertmanager-main-2   Bound    pvc-0d6413dc-15a5-11ea-baa0-026d231574aa   40Gi       RWO            ocs-storagecluster-ceph-rbd   8d
   persistentvolumeclaim/my-prometheus-claim-prometheus-k8s-0        Bound    pvc-0b7c19b0-15a5-11ea-baa0-026d231574aa   40Gi       RWO            ocs-storagecluster-ceph-rbd   8d
   persistentvolumeclaim/my-prometheus-claim-prometheus-k8s-1        Bound    pvc-0b8aed3f-15a5-11ea-baa0-026d231574aa   40Gi       RWO            ocs-storagecluster-ceph-rbd   8d

2. Edit the monitoring configmap.

   $ oc -n openshift-monitoring edit configmap cluster-monitoring-config

   Remove any config sections that reference the OpenShift Data Foundation storage classes as shown in the following example and save it.

   Before editing

   . . . apiVersion: v1 data: config.yaml: | alertmanagerMain: volumeClaimTemplate: metadata: name: my-alertmanager-claim spec: resources: requests: storage: 40Gi storageClassName: ocs-storagecluster-ceph-rbd prometheusK8s: volumeClaimTemplate: metadata: name: my-prometheus-claim spec: resources: requests: storage: 40Gi storageClassName: ocs-storagecluster-ceph-rbd kind: ConfigMap metadata: creationTimestamp: "2019-12-02T07:47:29Z" name: cluster-monitoring-config namespace: openshift-monitoring resourceVersion: "22110" selfLink: /api/v1/namespaces/openshift-monitoring/configmaps/cluster-monitoring-config uid: fd6d988b-14d7-11ea-84ff-066035b9efa8 . . .

   After editing

   . . . apiVersion: v1 data: config.yaml: | kind: ConfigMap metadata: creationTimestamp: "2019-11-21T13:07:05Z" name: cluster-monitoring-config namespace: openshift-monitoring resourceVersion: "404352" selfLink: /api/v1/namespaces/openshift-monitoring/configmaps/cluster-monitoring-config uid: d12c796a-0c5f-11ea-9832-063cd735b81c . . .

   In this example, alertmanagerMain and prometheusK8s monitoring components are using the OpenShift Data Foundation PVCs.

3. Delete the relevant PVCs. Make sure you delete all the PVCs that are consuming the storage classes.

   $ oc delete -n openshift-monitoring pvc <pvc-name> --wait=true --timeout=5m

   <pvc-name>

   Is the name of the PVC