Chapter 3. Uninstalling OpenShift Container Storage
Use the steps in this section to uninstall OpenShift Container Storage instead of the Uninstall option from the user interface.
Prerequisites
- Make sure that there are no consumers of OpenShift Container Storage.
- Make sure that the OpenShift Container Storage cluster is in 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 unhealthy state, you should contact Red Hat Customer Support before uninstalling OpenShift Container Storage.
- Delete any applications that are consuming persistent volume claims (PVCs) or object bucket claims (OBCs) based on the OpenShift Container Storage storage classes and then delete PVCs and OBCs that are using OpenShift Container Storage storage classes.
Procedure
List the storage classes and take a note of the storage classes with the following storage class provisioners:
-
openshift-storage.rbd.csi.ceph.com
-
openshift-storage.cephfs.csi.ceph.com
openshift-storage.noobaa.io/obc
For example
$ oc get storageclasses NAME PROVISIONER AGE gp2 (default) kubernetes.io/aws-ebs 23h ocs-storagecluster-ceph-rbd openshift-storage.rbd.csi.ceph.com 22h ocs-storagecluster-cephfs openshift-storage.cephfs.csi.ceph.com 22h openshift-storage.noobaa.io openshift-storage.noobaa.io/obc 22h
-
Query for PVCs and OBCs that are using the storage class provisioners listed in the previous step.
$ oc get pvc -o=jsonpath='{range .items[?(@.spec.storageClassName=="ocs-storagecluster-ceph-rbd")]}{"Name: "}{@.metadata.name}{" Namespace: "}{@.metadata.namespace}{"\n"}{end}' --all-namespaces|grep -v db-noobaa-core-0
$ oc get pvc -o=jsonpath='{range .items[?(@.spec.storageClassName=="ocs-storagecluster-cephfs")]}{"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
Follow these instructions to ensure that the PVCs listed in the previous step are deleted:
- Determine the pod that is consuming the PVC.
Identify the controlling object such as a
Deployment
,StatefulSet
,DeamonSet
,Job
, or a custom controller.Each object has a metadata field known as
OwnerReference
. This is a list of associated objects. TheOwnerReference
with thecontroller
field set totrue
will point to controlling objects such asReplicaSet
,StatefulSet
,DaemonSet
and so on.- Ensure that the object is safe to delete by asking the owner of the project and then delete it.
Delete the PVCs.
If you have created any PVCs as a part of configuring the monitoring stack, cluster logging operator, or prometheus registry, then you must perform the clean up steps provided in the following sections as required:
Delete the
StorageCluster
object without deleting its dependents.$ oc delete storagecluster --all -n openshift-storage --wait=true --timeout=5m --cascade=false
Delete
noobaa
resource and allow NooBaa PVC to be automatically deleted.Delete the
noobaa
resource.$ oc delete -n openshift-storage noobaa noobaa --wait=true --timeout=5m
Wait for the NooBaa PVC to be automatically deleted.
$ oc wait --for delete pvc -l noobaa-core=noobaa -n openshift-storage --timeout=5m
Delete the
CephCluster
resource and wait till the deletion is complete.$ oc delete -n openshift-storage cephcluster --all --wait=true --timeout=5m
Delete the namespaces and wait till the deletion is complete.
$ oc delete project openshift-storage --wait=true --timeout=5m
Delete the storage classes with an
openshift-storage
provisioner listed in step 1.$ oc delete storageclass <storageclass-name> --wait=true --timeout=5m
For example:
$ oc delete storageclass ocs-storagecluster-ceph-rbd ocs-storagecluster-cephfs openshift-storage.noobaa.io --wait=true --timeout=5m
Remove the taint from the storage nodes.
$ oc adm taint nodes --all node.ocs.openshift.io/storage-
Unlabel the storage nodes.
$ oc label nodes --all cluster.ocs.openshift.io/openshift-storage- $ oc label nodes --all topology.rook.io/rack-
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 --wait=true --timeout=5m
3.1. 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
PVCs are configured to use OpenShift Container Platform monitoring stack.
For information about configuring monitoring stack, see https://access.redhat.com/documentation/en-us/openshift_container_platform/4.2/html-single/monitoring/cluster-monitoring/configuring-the-monitoring-stack.html#configuring-the-cluster-monitoring-stack_configuring-monitoring.
Procedure
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-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
Edit the monitoring
configmap
.$ oc -n openshift-monitoring edit configmap cluster-monitoring-config
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-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
andprometheusK8s
monitoring components are using the OpenShift Container Storage PVCs.List the pods consuming the PVC.
In this example, the
alertmanagerMain
andprometheusK8s
pods that are consuming the PVCs are in theTerminating
state. You can delete the PVCs only after they are completely terminated.$ 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-storagecluster-ceph-rbd 19h persistentvolumeclaim/ocs-alertmanager-claim-alertmanager-main-1 Bound pvc-2ebeee54-1fed-11ea-93e1-0a88476a6a64 40Gi RWO ocs-storagecluster-ceph-rbd 19h persistentvolumeclaim/ocs-alertmanager-claim-alertmanager-main-2 Bound pvc-2ec6a9cf-1fed-11ea-93e1-0a88476a6a64 40Gi RWO ocs-storagecluster-ceph-rbd 19h persistentvolumeclaim/ocs-prometheus-claim-prometheus-k8s-0 Bound pvc-3162a80c-1fed-11ea-93e1-0a88476a6a64 40Gi RWO ocs-storagecluster-ceph-rbd 19h persistentvolumeclaim/ocs-prometheus-claim-prometheus-k8s-1 Bound pvc-316e99e2-1fed-11ea-93e1-0a88476a6a64 40Gi RWO ocs-storagecluster-ceph-rbd 19h
Delete relevant PVCs. Make sure you delete all the PVCs that are consuming the storage classes.
$ oc delete -n openshift-monitoring <pvc-name> --wait=true --timeout=5m
3.2. 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: https://access.redhat.com/documentation/en-us/openshift_container_platform/4.2/html-single/registry/architecture-component-imageregistry
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
Edit the
configs.imageregistry.operator.openshift.io
object and remove the content in the storage section.$ oc edit configs.imageregistry.operator.openshift.io
For AWS:
Before editing
. . . storage: pvc: claim: registry-cephfs-rwx-pvc . . .
After editing
. . . storage: . . .
In this example, the PVC is called
registry-cephfs-rwx-pvc
, which is now safe to delete.For VMware:
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.
Delete the PVC.
$ oc delete pvc <pvc-name> -n openshift-image-registry --wait=true --timeout=5m
3.3. 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
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.Delete PVCs.
$ oc delete pvc <pvc-name> -n openshift-logging --wait=true --timeout=5m