3.4.2. Removing monitoring stack from OpenShift Container Storage

Use this section to clean up the monitoring stack from OpenShift Container Storage.

The PVCs that are created as a part of configuring the monitoring stack are in the openshift-monitoring namespace.

Prerequisites

Procedure

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

    $ oc get pod,pvc -n openshift-monitoring
    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-external-storagecluster-ceph-rbd   8d
    persistentvolumeclaim/my-alertmanager-claim-alertmanager-main-1   Bound    pvc-0d5a9825-15a5-11ea-baa0-026d231574aa   40Gi       RWO            ocs-external-storagecluster-ceph-rbd   8d
    persistentvolumeclaim/my-alertmanager-claim-alertmanager-main-2   Bound    pvc-0d6413dc-15a5-11ea-baa0-026d231574aa   40Gi       RWO            ocs-external-storagecluster-ceph-rbd   8d
    persistentvolumeclaim/my-prometheus-claim-prometheus-k8s-0        Bound    pvc-0b7c19b0-15a5-11ea-baa0-026d231574aa   40Gi       RWO            ocs-external-storagecluster-ceph-rbd   8d
    persistentvolumeclaim/my-prometheus-claim-prometheus-k8s-1        Bound    pvc-0b8aed3f-15a5-11ea-baa0-026d231574aa   40Gi       RWO            ocs-external-storagecluster-ceph-rbd   8d
  2. Edit the monitoring configmap.

    $ oc -n openshift-monitoring edit configmap cluster-monitoring-config
  3. Remove any config sections that reference the OpenShift Container Storage 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-external-storagecluster-ceph-rbd
        prometheusK8s:
          volumeClaimTemplate:
            metadata:
              name: my-prometheus-claim
            spec:
              resources:
                requests:
                  storage: 40Gi
              storageClassName: ocs-external-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 Container Storage PVCs.

  4. List the pods consuming the PVC.

    In this example, the alertmanagerMain and prometheusK8s pods that were consuming the PVCs are in the Terminating state. You can delete the PVCs once these pods are no longer using OpenShift Container Storage PVC.

    $ oc get pod,pvc -n openshift-monitoring
    NAME                                               READY   STATUS      RESTARTS AGE
    pod/alertmanager-main-0                            3/3     Terminating   0      10h
    pod/alertmanager-main-1                            3/3     Terminating   0      10h
    pod/alertmanager-main-2                            3/3     Terminating   0      10h
    pod/cluster-monitoring-operator-84cd9df668-zhjfn   1/1     Running       0      18h
    pod/grafana-5db6fd97f8-pmtbf                       2/2     Running       0      10h
    pod/kube-state-metrics-895899678-z2r9q             3/3     Running       0      10h
    pod/node-exporter-4njxv                            2/2     Running       0      18h
    pod/node-exporter-b8ckz                            2/2     Running       0      11h
    pod/node-exporter-c2vp5                            2/2     Running       0      18h
    pod/node-exporter-cq65n                            2/2     Running       0      18h
    pod/node-exporter-f5sm7                            2/2     Running       0      11h
    pod/node-exporter-f852c                            2/2     Running       0      18h
    pod/node-exporter-l9zn7                            2/2     Running       0      11h
    pod/node-exporter-ngbs8                            2/2     Running       0      18h
    pod/node-exporter-rv4v9                            2/2     Running       0      18h
    pod/openshift-state-metrics-77d5f699d8-69q5x       3/3     Running       0      10h
    pod/prometheus-adapter-765465b56-4tbxx             1/1     Running       0      10h
    pod/prometheus-adapter-765465b56-s2qg2             1/1     Running       0      10h
    pod/prometheus-k8s-0                               6/6     Terminating   1      9m47s
    pod/prometheus-k8s-1                               6/6     Terminating   1      9m47s
    pod/prometheus-operator-cbfd89f9-ldnwc             1/1     Running       0      43m
    pod/telemeter-client-7b5ddb4489-2xfpz              3/3     Running       0      10h
    
    NAME                                                      STATUS  VOLUME                                     CAPACITY   ACCESS MODES   STORAGECLASS                  AGE
    persistentvolumeclaim/ocs-alertmanager-claim-alertmanager-main-0   Bound    pvc-2eb79797-1fed-11ea-93e1-0a88476a6a64   40Gi       RWO            ocs-external-storagecluster-ceph-rbd   19h
    persistentvolumeclaim/ocs-alertmanager-claim-alertmanager-main-1   Bound    pvc-2ebeee54-1fed-11ea-93e1-0a88476a6a64   40Gi       RWO            ocs-external-storagecluster-ceph-rbd   19h
    persistentvolumeclaim/ocs-alertmanager-claim-alertmanager-main-2   Bound    pvc-2ec6a9cf-1fed-11ea-93e1-0a88476a6a64   40Gi       RWO            ocs-external-storagecluster-ceph-rbd   19h
    persistentvolumeclaim/ocs-prometheus-claim-prometheus-k8s-0        Bound    pvc-3162a80c-1fed-11ea-93e1-0a88476a6a64   40Gi       RWO            ocs-external-storagecluster-ceph-rbd   19h
    persistentvolumeclaim/ocs-prometheus-claim-prometheus-k8s-1        Bound    pvc-316e99e2-1fed-11ea-93e1-0a88476a6a64   40Gi       RWO            ocs-external-storagecluster-ceph-rbd   19h
  5. Delete 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