Chapter 3. Uninstalling OpenShift Container Storage

Procedure

1. 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

2. 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}{" Labels: "}{@.metadata.labels}{"\n"}{end}' --all-namespaces|awk '! ( /Namespace: openshift-storage/ && /app:noobaa/ )'

   $ 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

   Note

   Ignore any NooBaa PVCs in the openshift-storage namespace.

3. Follow these instructions to ensure that the PVCs listed in the previous step are deleted:

   1. Determine the pod that is consuming the PVC.

   2. 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. 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 object is safe to delete by asking the owner of the project and then delete it.

   4. Delete the PVCs and OBCs.

      $ oc delete pvc <pvc name> -n <project-name>
      $ oc delete obc <obc name> -n <project name>

      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:

      • Section 3.1, “Removing monitoring stack from OpenShift Container Storage”
      • Section 3.2, “Removing OpenShift Container Platform registry from OpenShift Container Storage”
      • Section 3.3, “Removing the cluster logging operator from OpenShift Container Storage”

4. List and note the backing local volume objects. If no results found, then skip step 8 & 9.

   for sc in $(oc get storageclass|grep 'kubernetes.io/no-provisioner' |grep -E $(oc get storagecluster -n openshift-storage -o jsonpath='{ .items[*].spec.monPVCTemplate.spec.storageClassName } { .items[*].spec.storageDeviceSets[*].dataPVCTemplate.spec.storageClassName}' | sed 's/ /|/g')| awk '{ print $1 }');
   do
       echo -n "StorageClass: $sc ";
       oc get storageclass $sc -o jsonpath=" { 'LocalVolume: ' }{ .metadata.labels['local\.storage\.openshift\.io/owner-name'] } { '\n' }";
   done

   Example output

   StorageClass: localfile  LocalVolume: local-file
   StorageClass: localblock  LocalVolume: local-block

5. Delete the StorageCluster object.

   $ oc delete -n openshift-storage storagecluster --all --wait=true

6. Delete the namespace and wait till the deletion is complete.

   $ oc delete project openshift-storage --wait=true --timeout=5m

   Note

   You will need to switch to another project if openshift-storage was the active project.

   For example

   $ oc project default

7. Clean up the storage operator artifacts on each node.

   $ for i in $(oc get node -l cluster.ocs.openshift.io/openshift-storage= -o jsonpath='{ .items[*].metadata.name }'); do oc debug node/${i} -- chroot /host rm -rfv /var/lib/rook; done

   Ensure you see removed directory '/var/lib/rook' in the output.

   Example output

   Starting pod/ip-10-0-134-65us-east-2computeinternal-debug ...
   To use host binaries, run `chroot /host`
   removed '/var/lib/rook/openshift-storage/log/ocs-deviceset-2-0-gk22s/ceph-volume.log'
   removed directory '/var/lib/rook/openshift-storage/log/ocs-deviceset-2-0-gk22s'
   removed '/var/lib/rook/openshift-storage/log/ceph-osd.2.log'
   removed '/var/lib/rook/openshift-storage/log/ceph-volume.log'
   removed directory '/var/lib/rook/openshift-storage/log'
   removed directory '/var/lib/rook/openshift-storage/crash/posted'
   removed directory '/var/lib/rook/openshift-storage/crash'
   removed '/var/lib/rook/openshift-storage/client.admin.keyring'
   removed '/var/lib/rook/openshift-storage/openshift-storage.config'
   removed directory '/var/lib/rook/openshift-storage'
   removed '/var/lib/rook/osd2/openshift-storage.config'
   removed directory '/var/lib/rook/osd2'
   removed directory '/var/lib/rook'
   
   Removing debug pod ...
   Starting pod/ip-10-0-155-149us-east-2computeinternal-debug ...
   .
   .
   removed directory '/var/lib/rook'
   
   Removing debug pod ...
   Starting pod/ip-10-0-162-89us-east-2computeinternal-debug ...
   .
   .
   removed directory '/var/lib/rook'
   
   Removing debug pod ...

8. Delete the local volume created during the deployment and for each of the local volumes listed in step 4.

   For each of the local volumes, do the following:

   1. Set the variable LV to the name of the LocalVolume and variable SC to name of the StorageClass.

      For example

      $ LV=local-block
      $ SC=localblock

   2. List and note the devices to be cleaned up later.

      $ oc get localvolume -n local-storage $LV -o jsonpath='{ .spec.storageClassDevices[*].devicePaths[*] }'

      Example output

      /dev/disk/by-id/nvme-Amazon_Elastic_Block_Store_vol078f5cdde09efc165 /dev/disk/by-id/nvme-Amazon_Elastic_Block_Store_vol0defc1d5e2dd07f9e /dev/disk/by-id/nvme-Amazon_Elastic_Block_Store_vol0c8e82a3beeb7b7e5

   3. Delete the local volume resource.

      $ oc delete localvolume -n local-storage --wait=true $LV

   4. Delete the remaining PVs and StorageClasses if they exist.

      $ oc delete pv -l storage.openshift.com/local-volume-owner-name=${LV} --wait --timeout=5m
      $ oc delete storageclass $SC --wait --timeout=5m

   5. Clean up the artifacts from the storage nodes for that resource.

      $ [[ ! -z $SC ]] && for i in $(oc get node -l cluster.ocs.openshift.io/openshift-storage= -o jsonpath='{ .items[*].metadata.name }'); do oc debug node/${i} -- chroot /host rm -rfv /mnt/local-storage/${SC}/; done

      Example ouptut

      Starting pod/ip-10-0-141-2us-east-2computeinternal-debug ...
      To use host binaries, run `chroot /host`
      removed '/mnt/local-storage/localblock/nvme2n1'
      removed directory '/mnt/local-storage/localblock'
      
      Removing debug pod ...
      Starting pod/ip-10-0-144-55us-east-2computeinternal-debug ...
      To use host binaries, run `chroot /host`
      removed '/mnt/local-storage/localblock/nvme2n1'
      removed directory '/mnt/local-storage/localblock'
      
      Removing debug pod ...
      Starting pod/ip-10-0-175-34us-east-2computeinternal-debug ...
      To use host binaries, run `chroot /host`
      removed '/mnt/local-storage/localblock/nvme2n1'
      removed directory '/mnt/local-storage/localblock'
      
      Removing debug pod ...

9. Wipe the disks for each of the local volumes listed in step 4 so that they can be reused.

   1. List the storage nodes.

      $ oc get nodes -l cluster.ocs.openshift.io/openshift-storage=

      Example output

      NAME                                         STATUS   ROLES    AGE     VERSION
      ip-10-0-134-65.us-east-2.compute.internal    Ready    worker   4h45m   v1.17.1
      ip-10-0-155-149.us-east-2.compute.internal   Ready    worker   4h46m   v1.17.1
      ip-10-0-162-89.us-east-2.compute.internal    Ready    worker   4h45m   v1.17.1

   2. Obtain the node console and execute chroot /host command when the prompt appears.

      $ oc debug node/ip-10-0-134-65.us-east-2.compute.internal
      Starting pod/ip-10-0-134-65us-east-2computeinternal-debug ...
      To use host binaries, run `chroot /host`
      Pod IP: 10.0.134.65
      If you don't see a command prompt, try pressing enter.
      sh-4.2# chroot /host

   3. Store the disk paths gathered in step 8(ii) in the DISKS variable within quotes.

      sh-4.2# DISKS="/dev/disk/by-id/nvme-Amazon_Elastic_Block_Store_vol078f5cdde09efc165 /dev/disk/by-id/nvme-Amazon_Elasti_Block_Store_vol0defc1d5e2dd07f9e /dev/disk/by-id/nvme-Amazon_Elastic_Block_Store_vol0c8e82a3beeb7b7e5"

   4. Run sgdisk --zap-all on all the disks:

      sh-4.3# for disk in $DISKS; do sgdisk --zap-all $disk;done

      Example output

      Problem opening /dev/disk/by-id/nvme-Amazon_Elastic_Block_Store_vol078f5cdde09efc165 for reading! Error is 2.
      The specified file does not exist!
      Problem opening '' for writing! Program will now terminate.
      Warning! MBR not overwritten! Error is 2!
      Problem opening /dev/disk/by-id/nvme-Amazon_Elasti_Block_Store_vol0defc1d5e2dd07f9e for reading! Error is 2.
      The specified file does not exist!
      Problem opening '' for writing! Program will now terminate.
      Warning! MBR not overwritten! Error is 2!
      Creating new GPT entries.
      GPT data structures destroyed! You may now partition the disk using fdisk or
      other utilities.

      Note

      Ignore file-not-found warnings as they refer to disks that are on other machines.

   5. Exit the shell and repeat for the other nodes.

      sh-4.3# exit
      exit
      sh-4.2# exit
      exit
      
      Removing debug pod ...

10. 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

11. Unlabel the storage nodes.

    $ oc label nodes  --all cluster.ocs.openshift.io/openshift-storage-
    $ oc label nodes  --all topology.rook.io/rack-

    Note

    You can ignore the warnings displayed for the unlabeled nodes such as label <label> not found.

12. 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

13. To make sure that OpenShift Container Storage is uninstalled, verify that the openshift-storage namespace no longer exists and the storage dashboard no longer appears in the UI.