Deploying OpenShift Container Storage in external mode

Red Hat OpenShift Container Storage 4.5

How to install and set up your environment

Red Hat Storage Documentation Team

Abstract

Read this document for instructions on installing Red Hat OpenShift Container Storage 4.5 to use an external Red Hat Ceph Storage cluster.

Chapter 1. Overview of deploying in external mode

Red Hat OpenShift Container Storage can use an externally hosted Red Hat Ceph Storage (RHCS) cluster as the storage provider. This deployment type is supported for bare metal and user-provisioned VMware environments. See Planning your deployment for more information.

For instructions regarding how to install a RHCS 4 cluster, see Installation guide.

Follow these steps to deploy OpenShift Container Storage in external mode:

  1. If you use Red Hat Enterprise Linux hosts, Enable file system access for containers.

    Skip this step if you use Red Hat Enterprise Linux CoreOS (RHCOS) hosts.

  2. Install the OpenShift Container Storage Operator.
  3. Create the OpenShift Container Storage Cluster Service.

Chapter 2. Enabling file system access for containers on Red Hat Enterprise Linux based nodes

Deploying OpenShift Container Platform on a Red Hat Enterprise Linux base in a user provisioned infrastructure (UPI) does not automatically provide container access to the underlying Ceph file system.

Note

This process is not necessary for hosts based on Red Hat Enterprise Linux CoreOS.

Procedure

Perform the following steps on each node in your cluster.

  1. Log in to the Red Hat Enterprise Linux based node and open a terminal.
  2. Verify that the node has access to the rhel-7-server-extras-rpms repository.

    # subscription-manager repos --list-enabled | grep rhel-7-server

    If you do not see both rhel-7-server-rpms and rhel-7-server-extras-rpms in the output, or if there is no output, run the following commands to enable each repository.

    # subscription-manager repos --enable=rhel-7-server-rpms
    # subscription-manager repos --enable=rhel-7-server-extras-rpms
  3. Install the required packages.

    # yum install -y policycoreutils container-selinux
  4. Persistently enable container use of the Ceph file system in SELinux.

    # setsebool -P container_use_cephfs on

Chapter 3. Installing Red Hat OpenShift Container Storage Operator

You can install Red Hat OpenShift Container Storage Operator using the Red Hat OpenShift Container Platform Operator Hub. For information about the hardware and software requirements, see Planning your deployment.

Prerequisites

  • You must be logged into the OpenShift Container Platform cluster.
Note

When you need to override the cluster-wide default node selector for OpenShift Container Storage, you can use the following command in command line interface to specify a blank node selector for the openshift-storage namespace:

$ oc annotate namespace openshift-storage openshift.io/node-selector=

Procedure

  1. Click Operators → OperatorHub in the left pane of the OpenShift Web Console.

    Figure 3.1. List of operators in the Operator Hub

    Screenshot of list of operators in the Operator Hub of the OpenShift Web Console.
  2. Click on OpenShift Container Storage.

    You can use the Filter by keyword text box or the filter list to search for OpenShift Container Storage from the list of operators.

  3. On the OpenShift Container Storage operator page, click Install.
  4. On the Install Operator page, ensure the following options are selected:

    1. Update Channel as stable-4.5
    2. Installation Mode as A specific namespace on the cluster
    3. Installed Namespace as Operator recommended namespace PR openshift-storage. If Namespace openshift-storage does not exist, it will be created during the operator installation.
    4. Select Approval Strategy as Automatic or Manual. Approval Strategy is set to Automatic by default.

      • Approval Strategy as Automatic.

        Note

        When you select the Approval Strategy as Automatic, approval is not required either during fresh installation or when updating to the latest version of OpenShift Container Storage.

        1. Click Install
        2. Wait for the install to initiate. This may take up to 20 minutes.
        3. Click Operators → Installed Operators
        4. Ensure the Project is openshift-storage. By default, the Project is openshift-storage.
        5. Wait for the Status of OpenShift Container Storage to change to Succeeded.
      • Approval Strategy as Manual.

        Note

        When you select the Approval Strategy as Manual, approval is required during fresh installation or when updating to the latest version of OpenShift Container Storage.

        1. Click Install.
        2. On the Installed Operators page, click ocs-operator.
        3. On the Subscription Details page, click the Install Plan link.
        4. On the InstallPlan Details page, click Preview Install Plan.
        5. Review the install plan and click Approve.
        6. Wait for the Status of the Components to change from Unknown to either Created or Present.
        7. Click Operators → Installed Operators
        8. Ensure the Project is openshift-storage. By default, the Project is openshift-storage.
        9. Wait for the Status of OpenShift Container Storage to change to Succeeded.

Verification steps

  • Verify that OpenShift Container Storage Operator shows the Status as Succeeded on the Installed Operators dashboard.

Chapter 4. Creating an OpenShift Container Storage Cluster service for external mode

You need to create a new OpenShift Container Storage cluster service after you install OpenShift Container Storage operator on OpenShift Container Platform deployed on user provisioned infrastructures VMware vSphere or Bare metal platform.

Prerequisites

  • You must be logged into the working OpenShift Container Platform version 4.5.4 or above.
  • OpenShift Container Storage operator must be installed. For more information, see Installing OpenShift Container Storage Operator using the Operator Hub.
  • Red Hat Ceph Storage version 4.1.1 or later is required for the external cluster. For more information, see this knowledge base article on Red Hat Ceph Storage releases and corresponding Ceph package versions.

    If you have updated the Red Hat Ceph Storage cluster to version 4.1.1 or later from a previous release and is not a freshly deployed cluster, you must manually set the application type for CephFS pool on the Red Hat Ceph Storage cluster to enable CephFS PVC creation in external mode.

    For more details, see Troubleshooting CephFS PVC creation in external mode.

  • It is recommended that the external Red Hat Ceph Storage cluster has the PG Autoscaler enabled, with a target_size_ratio of 0.49. For more information, see The placement group autoscaler section in the Red Hat Ceph Storage documentation.
  • The external Ceph cluster should have an existing RBD pool pre-configured for use. If it does not exist, contact your Red Hat Ceph Storage administrator to create one before you move ahead with OpenShift Container Storage deployment.

Procedure

  1. Click Operators → Installed Operators from the OpenShift Web Console to view the installed operators. Ensure that the Project selected is openshift-storage.
  2. On the Installed Operators page, Click Openshift Container Storage.

    Figure 4.1. OpenShift Container Storage Operator page

    Screenshot of OpenShift Container Storage operator dashboard.
  3. On the Installed Operators → Operator Details page, perform either of the following to create a Storage Cluster Service.

    1. On the Details tab → Provided APIs → OCS Storage Cluster, click Create Instance.

      Figure 4.2. Operator Details Page

      Screenshot of Operator Details Page.
    2. Alternatively, select the Storage cluster tab and click Create OCS Cluster Service.

      Figure 4.3. Storage Cluster tab

      Screenshot of Storage Cluster tab on OpenShift Container Storage Operator dashboard.
  4. On the Create Storage Cluster page, ensure that the following options are selected:

    Figure 4.4. Connect to external cluster section on Create Storage Cluster form

    Screenshot shows connect to external cluster section after you select mode as external where you can download the python script and then upload the RHCS json file.
    1. Select Mode as External. By default, Internal is selected as deployment mode.
    2. In the Connect to external cluster section, click on the Download Script link to download the python script for extracting Ceph cluster details.
    3. For extracting the Red Hat Ceph Storage (RHCS) cluster details, contact the RHCS admin to run the downloaded python script on a Red Hat Ceph Storage client node.

      • Run the following command on the RHCS client node to view the list of available arguments.

        # python3 ceph-external-cluster-details-exporter.py --help
        Important

        Use python instead of python3 if the Red Hat Ceph Storage 4.x cluster is deployed on Red Hat Enterprise Linux 7.x (RHEL 7.x) cluster.

        Note

        If you do not have access to the RHCS client node, you can also run the script from inside a MON container (containerized deployment) or from a MON node (rpm deployment).

      • To retrieve the external cluster details from the RHCS cluster, run the following command

        # python3 ceph-external-cluster-details-exporter.py --rbd-data-pool-name <rbd block pool name> [optional arguments]

        For example

        # python3 ceph-external-cluster-details-exporter.py --rbd-data-pool-name ceph-rbd --rgw-endpoint xxx.xxx.xxx.xxx:xxxx --run-as-user client.ocs

        In the above example,

        • --rbd-data-pool-name is a mandatory parameter used for providing Block Storage in OpenShift Container Storage.
        • --rgw-endpoint is optional. Provide this parameter if object storage is to be provisioned through Ceph Rados Gateway for OpenShift Container Storage.
        • -- run-as-user is an optional parameter used for providing a name for the Ceph user which is created by the script. If this parameter is not specified, a default user name client.healthchecker is created. The permissions for the new user is set as:

          • caps: [mon] allow r, allow command quorum_status
          • caps: [osd] allow rwx pool=RGW_POOL_PREFIX.rgw.meta, allow r pool=.rgw.root, allow rw pool=RGW_POOL_PREFIX.rgw.control, allow x pool=RGW_POOL_PREFIX.rgw.buckets.index

            Example of JSON output generated using the python script:

            [{"name": "rook-ceph-mon-endpoints", "kind": "ConfigMap", "data": {"data": "ceph-mon-node=xxx.xxx.xxx.xxx:xxxx", "maxMonId": "0", "mapping": "{}"}}, {"name": "rook-ceph-mon", "kind": "Secret", "data": {"admin-secret": "<admin-secret>", "cluster-name": "openshift-storage", "fsid": "<fs-id>", "mon-secret": "<mon-secret>"}}, {"name": "rook-ceph-operator-creds", "kind": "Secret", "data": {"userID": "client.healthchecker", "userKey": "<user-key>"}}, {"name": "rook-csi-rbd-node", "kind": "Secret", "data": {"userID": "csi-rbd-node", "userKey": "<user-key>"}}, {"name": "rook-csi-rbd-provisioner", "kind": "Secret", "data": {"userID": "csi-rbd-provisioner", "userKey": "<user-key>"}}, {"name": "rook-csi-cephfs-node", "kind": "Secret", "data": {"adminID": "csi-cephfs-node", "adminKey": "<admin-key>"}}, {"name": "rook-csi-cephfs-provisioner", "kind": "Secret", "data": {"adminID": "csi-cephfs-provisioner", "adminKey": "<admin-key>"}}, {"name": "ceph-rbd", "kind": "StorageClass", "data": {"pool": "ceph-rbd"}}, {"name": "cephfs", "kind": "StorageClass", "data": {"fsName": "cephfs", "pool": "cephfs_data"}}, {"name": "ceph-rgw", "kind": "StorageClass", "data": {"endpoint": "xxx.xxx.xxx.xxx:xxxx"}}]

      • Save the JSON output to a file with .json extension

        Note

        For OpenShift Container Storage to work seamlessly, ensure that the parameters (RGW endpoint, CephFS details, RBD pool, etc.) to be uploaded using the JSON file remains unchanged on the RHCS external cluster, post storage cluster creation.

    4. Click External cluster metadata → Browse to select and upload the json file. The json file content will be populated and displayed in the text box.

      Figure 4.5. Json file content

      Screenshot shows the content of the credentials file after it is uploaded
  5. Click Create.

    Note

    The Create button is enabled only after you upload the .json file.

Verification steps

Chapter 5. Verifying your OpenShift Container Storage installation for external mode

Use this section to verify that OpenShift Container Storage is deployed correctly.

5.1. Verify that the pods are in running state

  1. Click Workloads → Pods from the left pane of the OpenShift Web Console.
  2. Select openshift-storage from the Project drop down list.

    For more information on the expected number of pods for each component and how it varies depending on the number of nodes, see Table 5.1, “Pods corresponding to OpenShift Container Storage components”

  3. Verify that the following pods are in running state:

    Table 5.1. Pods corresponding to OpenShift Container Storage components

    ComponentCorresponding pods

    OpenShift Container Storage Operator

    ocs-operator-*

    (1 pod on any worker node)

    Rook-ceph Operator

    rook-ceph-operator-*

    (1 pod on any worker node)

    Multicloud Object Gateway

    • noobaa-operator-* (1 pod on any worker node)
    • noobaa-core-* (1 pod on any worker node)
    • nooba-db-* (1 pod on any worker node)
    • noobaa-endpoint-* (1 pod on any worker node)

    CSI

    • cephfs

      • csi-cephfsplugin-* (1 pod on each worker node)
      • csi-cephfsplugin-provisioner-* (2 pods distributed across worker nodes)
    • rbd

      • csi-rbdplugin-* (1 pod on each worker node)
      • csi-rbdplugin-provisioner-* (2 pods distributed across worker nodes)

5.2. Verify that the OpenShift Container Storage cluster is healthy

  • Click Home → Overview from the left pane of the OpenShift Web Console and click Persistent Storage tab.
  • In the Status card, verify that OCS Cluster has a green tick mark as shown in the following image:

    Figure 5.1. Health status card in Persistent Storage Overview Dashboard

    Screenshot of status card showing external cluster health in persistent storage dashboard
  • In the Details card, verify that the cluster information is displayed appropriately as follows:

    Figure 5.2. Details card in Persistent Storage Overview Dashboard

    Screenshot of Details card in persistent storage dashboard for external mode

For more information on verifying the health of OpenShift Container Storage cluster using the persistent storage dashboard, see Monitoring OpenShift Container Storage.

5.3. Verify that the Multicloud Object Gateway is healthy

  • Click Home → Overview from the left pane of the OpenShift Web Console and click the Object Service tab.
  • In the Status card, verify that the Multicloud Object Gateway (MCG) storage displays a green tick icon as shown in following image:

    Figure 5.3. Health status card in Object Service Overview Dashboard

    Screenshot of Health card in object service dashboard
  • In the Details card, verify that the MCG information is displayed appropriately as follows:

    Figure 5.4. Details card in Object Service Overview Dashboard

    Screenshot of Details card in object service dashboard

For more information on verifying the health of OpenShift Container Storage cluster using the object service dashboard, see Monitoring OpenShift Container Storage.

5.4. Verify that the storage classes are created and listed

  • Click Storage → Storage Classes from the left pane of the OpenShift Web Console.
  • Verify that the following storage classes are created with the OpenShift Container Storage cluster creation:

    • ocs-external-storagecluster-ceph-rbd
    • ocs-external-storagecluster-ceph-rgw
    • ocs-external-storagecluster-cephfs
    • openshift-storage.noobaa.io
Note
  • If an MDS is not deployed in the external cluster, ocs-external-storagecluster-cephfs storage class will not be created.
  • If an RGW is not deployed in the external cluster, the ocs-external-storagecluster-ceph-rgw storage class will not be created.

For more information regarding MDS and RGW, see Red Hat Ceph Storage documentation

5.5. Verify that Ceph cluster is connected

Run the following command to verify if the OpenShift Container Storage cluster is connected to Ceph cluster.

$ oc get cephcluster -n openshift-storage
NAME                                      DATADIRHOSTPATH     MONCOUNT    AGE      PHASE       MESSAGE                         HEALTH
ocs-external-storagecluster-cephcluster                                   31m15s   Connected   Cluster connected successfully  HEALTH_OK

5.6. Verify that storage cluster is ready

Run the following command to verify if the storage cluster is ready and the External option is set to true.

$ oc get storagecluster -n openshift-storage
NAME                        AGE      PHASE EXTERNAL  CREATED AT              VERSION
ocs-external-storagecluster 31m15s   Ready true      2020-07-29T20:43:04Z    4.5.0

Chapter 6. Uninstalling OpenShift Container Storage

6.1. Uninstalling OpenShift Container Storage on External mode

Use the steps in this section to uninstall OpenShift Container Storage instead of the Uninstall option from the user interface. Uninstalling OpenShift Container Storage will neither remove the RBD pool from the external cluster nor uninstall the external RedHat Ceph Storage cluster.

Prerequisites

  • Make sure that the OpenShift Container Storage cluster is in a healthy state. The deletion might fail if some of the pods are not terminated successfully due to insufficient resources or nodes. In case the cluster is in an unhealthy state, you should contact Red Hat Customer Support before uninstalling OpenShift Container Storage.
  • Make sure that applications are not consuming persistent volume claims (PVCs) or object bucket claims (OBCs) using the storage classes provided by OpenShift Container Storage. PVCs and OBCs will be deleted during the uninstall process.

Procedure

  1. Query for PVCs and OBCs that use the OpenShift Container Storage based storage class provisioners.

    For example :

    $ oc get pvc -o=jsonpath='{range .items[?(@.spec.storageClassName=="ocs-external-storagecluster-ceph-rbd")]}{"Name: "}{@.metadata.name}{" Namespace: "}{@.metadata.namespace}{" Labels: "}{@.metadata.labels}{"\n"}{end}' --all-namespaces|awk '! ( /Namespace: openshift-storage/ && /app:noobaa/ )' | grep -v noobaa-default-backing-store-noobaa-pvc
    Note

    If the external RedHat Ceph Storage cluster is not configured for CephFS, you can ignore the following query command for ocs-external-storagecluster-cephfs.

    $ oc get pvc -o=jsonpath='{range .items[?(@.spec.storageClassName=="ocs-external-storagecluster-cephfs")]}{"Name: "}{@.metadata.name}{" Namespace: "}{@.metadata.namespace}{"\n"}{end}' --all-namespaces
    Note

    If the external RedHat Ceph Storage cluster is not configured for Object Storage, you can ignore the following query command for ocs-external-storagecluster-ceph-rgw.

    $ oc get obc -o=jsonpath='{range .items[?(@.spec.storageClassName=="ocs-external-storagecluster-ceph-rgw")]}{"Name: "}{@.metadata.name}{" Namespace: "}{@.metadata.namespace}{"\n"}{end}' --all-namespaces
    $ oc get obc -o=jsonpath='{range .items[?(@.spec.storageClassName=="openshift-storage.noobaa.io")]}{"Name: "}{@.metadata.name}{" Namespace: "}{@.metadata.namespace}{"\n"}{end}' --all-namespaces
  2. Follow these instructions to ensure the PVCs and OBCs listed in the previous step are deleted.

    If you have created PVCs as a part of configuring the monitoring stack, cluster logging operator, or image registry, then you must perform the clean up steps provided in the following sections as required:

    • Section 6.2, “Removing monitoring stack from OpenShift Container Storage”
    • Section 6.3, “Removing OpenShift Container Platform registry from OpenShift Container Storage”
    • Section 6.4, “Removing the cluster logging operator from OpenShift Container Storage”

      For each of the remaining PVCs or OBCs, follow the steps mentioned below:

      1. Determine the pod that is consuming the PVC or OBC.
      2. Identify the controlling API object such as a Deployment, StatefulSet, DaemonSet , Job, or a custom controller.

        Each API object has a metadata field known as OwnerReference. This is a list of associated objects. The OwnerReference with the controller field set to true will point to controlling objects such as ReplicaSet, StatefulSet,DaemonSet and so on.

      3. Ensure that the API object is not consuming PVC or OBC provided by OpenShift Container Storage. Either the object should be deleted or the storage should be replaced. Ask the owner of the project to make sure that it is safe to delete or modify the object.

        Note

        You can ignore the noobaa pods.

      4. Delete the OBCs.

        $ oc delete obc <obc name> -n <project name>
      5. Delete any custom Bucket Class you have created.

        $ oc get bucketclass -A | grep -v noobaa-default-bucket-class
        $ oc delete bucketclass <bucketclass name> -n <project-name>
      6. If you have created any custom Multi Cloud Gateway backingstores, delete each of them.

        1. List and note the backingstores.

          for bs in $(oc get backingstore -o name -n openshift-storage | grep -v noobaa-default-backing-store); do echo "Found backingstore $bs"; echo "Its has the following pods running :"; echo "$(oc get pods -o name -n openshift-storage | grep $(echo ${bs} | cut -f2 -d/))"; done
        2. Delete each of the backingstores listed above and confirm that the corresponding pods and PVCs are deleted.

          for bs in $(oc get backingstore -o name -n openshift-storage | grep -v noobaa-default-backing-store); do echo "Deleting Backingstore $bs"; oc delete -n openshift-storage $bs; done
        3. If any of the backingstores listed above were based on the pv-pool, ensure that the corresponding pod and PVC are also deleted.

          $ oc get pods  -n openshift-storage | grep noobaa-pod | grep -v noobaa-default-backing-store-noobaa-pod
          $ oc get pvc -n openshift-storage --no-headers | grep -v noobaa-db | grep -v noobaa-default-backing-store-noobaa-pvc
      7. Delete the remaining PVCs listed in Step 1.

        $ oc delete pvc <pvc name> -n <project-name>
  3. Delete the StorageCluster object and wait for the removal of the associated resources.

    $ oc delete -n openshift-storage storagecluster --all --wait=true
  4. Delete the namespace and wait till the deletion is complete. You will need to switch to another project if openshift-storage is the active project.

    1. Switch to another namespace if openshift-storage is the active namespace.

      For example :

      $ oc project default
    2. Delete the openshift-storage namespace.

      $ oc delete project openshift-storage --wait=true --timeout=5m
    3. Wait for approximately five minutes and confirm if the project is deleted successfully.

      $ oc get project  openshift-storage

      Output:

      Error from server (NotFound): namespaces "openshift-storage" not found
      Note

      While uninstalling OpenShift Container Storage, if namespace is not deleted completely and remains in Terminating state, perform the steps in the article Troubleshooting and deleting remaining resources during Uninstall to identify objects that are blocking the namespace from being terminated.

  5. Delete the openshift-storage.noobaa.io storage class.

    $ oc delete storageclass  openshift-storage.noobaa.io --wait=true --timeout=5m
  6. Confirm all PVs are deleted. If there is any PV left in the Released state, delete it.

    # oc get pv|egrep 'ocs-external-storagecluster-ceph-rbd|ocs-external-storagecluster-cephfs'
    # oc  delete pv <pv name>
  7. Remove CustomResourceDefinitions.

    $ oc delete crd backingstores.noobaa.io bucketclasses.noobaa.io cephblockpools.ceph.rook.io cephclusters.ceph.rook.io cephfilesystems.ceph.rook.io cephnfses.ceph.rook.io cephobjectstores.ceph.rook.io cephobjectstoreusers.ceph.rook.io noobaas.noobaa.io ocsinitializations.ocs.openshift.io  storageclusterinitializations.ocs.openshift.io storageclusters.ocs.openshift.io cephclients.ceph.rook.io --wait=true --timeout=5m
  8. To ensure that OpenShift Container Storage is uninstalled completely, on the OpenShift Container Platform Web Console,

    1. Click HomeOverview to access the dashboard.
    2. Verify that the Persistent Storage and Object Service tabs no longer appear next to the Cluster tab.

6.2. Removing monitoring stack from OpenShift Container Storage

Use this section to clean up 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

6.3. Removing OpenShift Container Platform registry from OpenShift Container Storage

Use this section to clean up OpenShift Container Platform registry from OpenShift Container Storage. If you want to configure an alternative storage, see image registry

The PVCs that are created as a part of configuring OpenShift Container Platform registry are in the openshift-image-registry namespace.

Prerequisites

  • The image registry should have been configured to use an OpenShift Container Storage PVC.

Procedure

  1. Edit the configs.imageregistry.operator.openshift.io object and remove the content in the storage section.

    $ oc edit configs.imageregistry.operator.openshift.io

    Before editing

    .
    .
    .
    storage:
      pvc:
        claim: registry-cephfs-rwx-pvc
    .
    .
    .

    After editing

    .
    .
    .
    storage:
      emptyDir: {}
    .
    .
    .

    In this example, the PVC is called registry-cephfs-rwx-pvc, which is now safe to delete.

  2. Delete the PVC.

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

6.4. Removing the cluster logging operator from OpenShift Container Storage

Use this section to clean up the cluster logging operator from OpenShift Container Storage.

The PVCs that are created as a part of configuring cluster logging operator are in openshift-logging namespace.

Prerequisites

  • The cluster logging instance should have been configured to use OpenShift Container Storage PVCs.

Procedure

  1. Remove the ClusterLogging instance in the namespace.

    $ oc delete clusterlogging instance -n openshift-logging --wait=true --timeout=5m

    The PVCs in the openshift-logging namespace are now safe to delete.

  2. Delete PVCs.

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