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Replacing devices

Red Hat OpenShift Data Foundation 4.12

Instructions for safely replacing operational or failed devices

Red Hat Storage Documentation Team

Abstract

This document explains how to safely replace storage devices for Red Hat OpenShift Data Foundation.

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Preface

Depending on the type of your deployment, you can choose one of the following procedures to replace a storage device:

Note

OpenShift Data Foundation does not support heterogeneous OSD sizes.

Chapter 1. Dynamically provisioned OpenShift Data Foundation deployed on AWS

1.1. Replacing operational or failed storage devices on AWS user-provisioned infrastructure

When you need to replace a device in a dynamically created storage cluster on an AWS user-provisioned infrastructure, you must replace the storage node. For information about how to replace nodes, see:

1.2. Replacing operational or failed storage devices on AWS installer-provisioned infrastructure

When you need to replace a device in a dynamically created storage cluster on an AWS installer-provisioned infrastructure, you must replace the storage node. For information about how to replace nodes, see:

Chapter 2. Dynamically provisioned OpenShift Data Foundation deployed on VMware

2.1. Replacing operational or failed storage devices on VMware infrastructure

Create a new Persistent Volume Claim (PVC) on a new volume, and remove the old object storage device (OSD) when one or more virtual machine disks (VMDK) needs to be replaced in OpenShift Data Foundation which is deployed dynamically on VMware infrastructure.

Prerequisites

  • Ensure that the data is resilient.

    • In the OpenShift Web Console, click Storage → Data Foundation.
    • Click the Storage Systems tab, and then click ocs-storagecluster-storagesystem.
    • In the Status card of Block and File dashboard, under the Overview tab, verify that Data Resiliency has a green tick mark.

Procedure

  1. Identify the OSD that needs to be replaced and the OpenShift Container Platform node that has the OSD scheduled on it. 

    $ oc get -n openshift-storage pods -l app=rook-ceph-osd -o wide
    Copy to Clipboard

    Example output: 

    rook-ceph-osd-0-6d77d6c7c6-m8xj6    0/1    CrashLoopBackOff    0    24h   10.129.0.16   compute-2   <none>           <none>
rook-ceph-osd-1-85d99fb95f-2svc7    1/1    Running             0    24h   10.128.2.24   compute-0   <none>           <none>
rook-ceph-osd-2-6c66cdb977-jp542    1/1    Running             0    24h   10.130.0.18   compute-1   <none>           <none>
    Copy to Clipboard

    In this example, rook-ceph-osd-0-6d77d6c7c6-m8xj6 needs to be replaced and compute-2 is the OpenShift Container platform node on which the OSD is scheduled.

    Note

    If the OSD to be replaced is healthy, the status of the pod will be Running.

  2. Scale down the OSD deployment for the OSD to be replaced.

    Each time you want to replace the OSD, update the osd_id_to_remove parameter with the OSD ID, and repeat this step. 

    $ osd_id_to_remove=0
    Copy to Clipboard 
    $ oc scale -n openshift-storage deployment rook-ceph-osd-${osd_id_to_remove} --replicas=0
    Copy to Clipboard

    where, osd_id_to_remove is the integer in the pod name immediately after the rook-ceph-osd prefix. In this example, the deployment name is rook-ceph-osd-0.

    Example output: 

    deployment.extensions/rook-ceph-osd-0 scaled
    Copy to Clipboard

  3. Verify that the rook-ceph-osd pod is terminated. 

    $ oc get -n openshift-storage pods -l ceph-osd-id=${osd_id_to_remove}
    Copy to Clipboard

    Example output: 

    No resources found.
    Copy to Clipboard
    Important

    If the rook-ceph-osd pod is in terminating state, use the force option to delete the pod. 

    $ oc delete pod rook-ceph-osd-0-6d77d6c7c6-m8xj6 --force --grace-period=0
    Copy to Clipboard

    Example output: 

    warning: Immediate deletion does not wait for confirmation that the running resource has been terminated. The resource may continue to run on the cluster indefinitely.
  pod "rook-ceph-osd-0-6d77d6c7c6-m8xj6" force deleted
    Copy to Clipboard

  4. Remove the old OSD from the cluster so that you can add a new OSD.

    1. Delete any old ocs-osd-removal jobs. 

      $ oc delete -n openshift-storage job ocs-osd-removal-job
      Copy to Clipboard

      Example output: 

      job.batch "ocs-osd-removal-job" deleted
      Copy to Clipboard

    2. Navigate to the openshift-storage project. 

      $ oc project openshift-storage
      Copy to Clipboard

    3. Remove the old OSD from the cluster. 

      $ oc process -n openshift-storage ocs-osd-removal -p FAILED_OSD_IDS=${osd_id_to_remove} -p FORCE_OSD_REMOVAL=false |oc create -n openshift-storage -f -
      Copy to Clipboard

      The FORCE_OSD_REMOVAL value must be changed to “true” in clusters that only have three OSDs, or clusters with insufficient space to restore all three replicas of the data after the OSD is removed.

      Warning

      This step results in OSD being completely removed from the cluster. Ensure that the correct value of osd_id_to_remove is provided.

  5. Verify that the OSD was removed successfully by checking the status of the ocs-osd-removal-job pod.

    A status of Completed confirms that the OSD removal job succeeded. 

    $ oc get pod -l job-name=ocs-osd-removal-job -n openshift-storage
    Copy to Clipboard

  6. Ensure that the OSD removal is completed. 

    $ oc logs -l job-name=ocs-osd-removal-job -n openshift-storage --tail=-1 | egrep -i 'completed removal'
    Copy to Clipboard

    Example output: 

    2022-05-10 06:50:04.501511 I | cephosd: completed removal of OSD 0
    Copy to Clipboard
    Important

    If the ocs-osd-removal-job pod fails and the pod is not in the expected Completed state, check the pod logs for further debugging.

    For example: 

    # oc logs -l job-name=ocs-osd-removal-job -n openshift-storage --tail=-1
    Copy to Clipboard

  7. If encryption was enabled at the time of install, remove dm-crypt managed device-mapper mapping from the OSD devices that are removed from the respective OpenShift Data Foundation nodes.

    1. Get the PVC name(s) of the replaced OSD(s) from the logs of ocs-osd-removal-job pod. 

      $ oc logs -l job-name=ocs-osd-removal-job -n openshift-storage --tail=-1  |egrep -i ‘pvc|deviceset’
      Copy to Clipboard

      Example output: 

      2021-05-12 14:31:34.666000 I | cephosd: removing the OSD PVC "ocs-deviceset-xxxx-xxx-xxx-xxx"
      Copy to Clipboard

    2. For each of the previously identified nodes, do the following:

      1. Create a debug pod and chroot to the host on the storage node. 

        $ oc debug node/<node name>
        Copy to Clipboard
        <node name>

        Is the name of the node. 

        $ chroot /host
        Copy to Clipboard

      2. Find a relevant device name based on the PVC names identified in the previous step. 

        $ dmsetup ls| grep <pvc name>
        Copy to Clipboard
        <pvc name>

        Is the name of the PVC.

        Example output: 

        ocs-deviceset-xxx-xxx-xxx-xxx-block-dmcrypt (253:0)
        Copy to Clipboard

      3. Remove the mapped device. 

        $ cryptsetup luksClose --debug --verbose ocs-deviceset-xxx-xxx-xxx-xxx-block-dmcrypt
        Copy to Clipboard
        Important

        If the above command gets stuck due to insufficient privileges, run the following commands:

        • Press CTRL+Z to exit the above command.

        • Find the PID of the process which was stuck. 

          $ ps -ef | grep crypt
          Copy to Clipboard

        • Terminate the process using the kill command. 

          $ kill -9 <PID>
          Copy to Clipboard
          <PID>
          Is the process ID.

        • Verify that the device name is removed. 

          $ dmsetup ls
          Copy to Clipboard

  8. Delete the ocs-osd-removal job. 

    $ oc delete -n openshift-storage job ocs-osd-removal-job
    Copy to Clipboard

    Example output: 

    job.batch "ocs-osd-removal-job" deleted
    Copy to Clipboard
Note

When using an external key management system (KMS) with data encryption, the old OSD encryption key can be removed from the Vault server as it is now an orphan key.

Verfication steps

  1. Verify that there is a new OSD running. 

    $ oc get -n openshift-storage pods -l app=rook-ceph-osd
    Copy to Clipboard

    Example output: 

    rook-ceph-osd-0-5f7f4747d4-snshw                                  1/1     Running     0          4m47s
rook-ceph-osd-1-85d99fb95f-2svc7                                  1/1     Running     0          1d20h
rook-ceph-osd-2-6c66cdb977-jp542                                  1/1     Running     0          1d20h
    Copy to Clipboard

  2. Verify that there is a new PVC created which is in Bound state. 

    $ oc get -n openshift-storage pvc
    Copy to Clipboard

    Example output: 

    NAME                      STATUS   VOLUME                                     CAPACITY   ACCESS MODES   STORAGECLASS    AGE
ocs-deviceset-0-0-2s6w4   Bound    pvc-7c9bcaf7-de68-40e1-95f9-0b0d7c0ae2fc   512Gi      RWO            thin            5m
ocs-deviceset-1-0-q8fwh   Bound    pvc-9e7e00cb-6b33-402e-9dc5-b8df4fd9010f   512Gi      RWO            thin            1d20h
ocs-deviceset-2-0-9v8lq   Bound    pvc-38cdfcee-ea7e-42a5-a6e1-aaa6d4924291   512Gi      RWO            thin            1d20h
    Copy to Clipboard

  3. Optional: If cluster-wide encryption is enabled on the cluster, verify that the new OSD devices are encrypted.

    1. Identify the nodes where the new OSD pods are running. 

      $ oc get -n openshift-storage -o=custom-columns=NODE:.spec.nodeName pod/<OSD-pod-name>
      Copy to Clipboard
      <OSD-pod-name>

      Is the name of the OSD pod.

      For example: 

      $ oc get -n openshift-storage -o=custom-columns=NODE:.spec.nodeName pod/rook-ceph-osd-0-544db49d7f-qrgqm
      Copy to Clipboard

      Example output: 

      NODE
compute-1
      Copy to Clipboard

    2. For each of the nodes identified in the previous step, do the following:

      1. Create a debug pod and open a chroot environment for the selected host(s). 

        $ oc debug node/<node name>
        Copy to Clipboard
        <node name>

        Is the name of the node. 

        $ chroot /host
        Copy to Clipboard

      2. Check for the crypt keyword beside the ocs-deviceset name(s). 

        $ lsblk
        Copy to Clipboard
  4. Log in to OpenShift Web Console and view the storage dashboard.

Chapter 3. Dynamically provisioned OpenShift Data Foundation deployed on Red Hat Virtualization

3.1. Replacing operational or failed storage devices on Red Hat Virtualization installer-provisioned infrastructure

Create a new Persistent Volume Claim (PVC) on a new volume, and remove the old object storage device (OSD).

Prerequisites

  • Ensure that the data is resilient.

    • In the OpenShift Web Console, click Storage → Data Foundation.
    • Click the Storage Systems tab, and then click ocs-storagecluster-storagesystem.
    • In the Status card of Block and File dashboard, under the Overview tab, verify that Data Resiliency has a green tick mark.

Procedure

  1. Identify the OSD that needs to be replaced and the OpenShift Container Platform node that has the OSD scheduled on it. 

    $ oc get -n openshift-storage pods -l app=rook-ceph-osd -o wide
    Copy to Clipboard

    Example output: 

    rook-ceph-osd-0-6d77d6c7c6-m8xj6    0/1    CrashLoopBackOff    0    24h   10.129.0.16   compute-2   <none>           <none>
rook-ceph-osd-1-85d99fb95f-2svc7    1/1    Running             0    24h   10.128.2.24   compute-0   <none>           <none>
rook-ceph-osd-2-6c66cdb977-jp542    1/1    Running             0    24h   10.130.0.18   compute-1   <none>           <none>
    Copy to Clipboard

    In this example, rook-ceph-osd-0-6d77d6c7c6-m8xj6 needs to be replaced and compute-2 is the OpenShift Container platform node on which the OSD is scheduled.

    Note

    If the OSD to be replaced is healthy, the status of the pod will be Running.

  2. Scale down the OSD deployment for the OSD to be replaced.

    Each time you want to replace the OSD, update the osd_id_to_remove parameter with the OSD ID, and repeat this step. 

    $ osd_id_to_remove=0
    Copy to Clipboard 
    $ oc scale -n openshift-storage deployment rook-ceph-osd-${osd_id_to_remove} --replicas=0
    Copy to Clipboard

    where, osd_id_to_remove is the integer in the pod name immediately after the rook-ceph-osd prefix. In this example, the deployment name is rook-ceph-osd-0.

    Example output: 

    deployment.extensions/rook-ceph-osd-0 scaled
    Copy to Clipboard

  3. Verify that the rook-ceph-osd pod is terminated. 

    $ oc get -n openshift-storage pods -l ceph-osd-id=${osd_id_to_remove}
    Copy to Clipboard

    Example output: 

    No resources found.
    Copy to Clipboard
    Important

    If the rook-ceph-osd pod is in terminating state, use the force option to delete the pod. 

    $ oc delete pod rook-ceph-osd-0-6d77d6c7c6-m8xj6 --force --grace-period=0
    Copy to Clipboard

    Example output: 

    warning: Immediate deletion does not wait for confirmation that the running resource has been terminated. The resource may continue to run on the cluster indefinitely.
  pod "rook-ceph-osd-0-6d77d6c7c6-m8xj6" force deleted
    Copy to Clipboard

  4. Remove the old OSD from the cluster so that you can add a new OSD.

    1. Delete any old ocs-osd-removal jobs. 

      $ oc delete -n openshift-storage job ocs-osd-removal-job
      Copy to Clipboard

      Example output: 

      job.batch "ocs-osd-removal-job"
      Copy to Clipboard

    2. Navigate to the openshift-storage project. 

      $ oc project openshift-storage
      Copy to Clipboard

    3. Remove the old OSD from the cluster. 

      $ oc process -n openshift-storage ocs-osd-removal -p FAILED_OSD_IDS=${osd_id_to_remove} -p FORCE_OSD_REMOVAL=false |oc create -n openshift-storage -f -
      Copy to Clipboard

      The FORCE_OSD_REMOVAL value must be changed to “true” in clusters that only have three OSDs, or clusters with insufficient space to restore all three replicas of the data after the OSD is removed.

      Warning

      This step results in OSD being completely removed from the cluster. Ensure that the correct value of osd_id_to_remove is provided.

  5. Verify that the OSD was removed successfully by checking the status of the ocs-osd-removal-job pod.

    A status of Completed confirms that the OSD removal job succeeded. 

    $ oc get pod -l job-name=ocs-osd-removal-job -n openshift-storage
    Copy to Clipboard

  6. Ensure that the OSD removal is completed. 

    $ oc logs -l job-name=ocs-osd-removal-job -n openshift-storage --tail=-1 | egrep -i 'completed removal'
    Copy to Clipboard

    Example output: 

    2022-05-10 06:50:04.501511 I | cephosd: completed removal of OSD 0
    Copy to Clipboard
    Important

    If the ocs-osd-removal-job fails and the pod is not in the expected Completed state, check the pod logs for further debugging.

    For example: 

    # oc logs -l job-name=ocs-osd-removal-job -n openshift-storage --tail=-1'
    Copy to Clipboard

  7. If encryption was enabled at the time of install, remove dm-crypt managed device-mapper mapping from the OSD devices that are removed from the respective OpenShift Data Foundation nodes.

    1. Get the PVC name(s) of the replaced OSD(s) from the logs of ocs-osd-removal-job pod. 

      $ oc logs -l job-name=ocs-osd-removal-job -n openshift-storage --tail=-1  |egrep -i ‘pvc|deviceset’
      Copy to Clipboard

      Example output: 

      2021-05-12 14:31:34.666000 I | cephosd: removing the OSD PVC "ocs-deviceset-xxxx-xxx-xxx-xxx"
      Copy to Clipboard

    2. For each of the previously identified nodes, do the following:

      1. Create a debug pod and chroot to the host on the storage node. 

        $ oc debug node/<node name>
        Copy to Clipboard
        <node name>

        Is the name of the node. 

        $ chroot /host
        Copy to Clipboard

      2. Find a relevant device name based on the PVC names identified in the previous step. 

        $ dmsetup ls| grep <pvc name>
        Copy to Clipboard
        <pvc name>

        Is the name of the PVC.

        Example output: 

        ocs-deviceset-xxx-xxx-xxx-xxx-block-dmcrypt (253:0)
        Copy to Clipboard

      3. Remove the mapped device. 

        $ cryptsetup luksClose --debug --verbose ocs-deviceset-xxx-xxx-xxx-xxx-block-dmcrypt
        Copy to Clipboard
        Important

        If the above command gets stuck due to insufficient privileges, run the following commands:

        • Press CTRL+Z to exit the above command.

        • Find the PID of the process which was stuck. 

          $ ps -ef | grep crypt
          Copy to Clipboard

        • Terminate the process using the kill command. 

          $ kill -9 <PID>
          Copy to Clipboard
          <PID>
          Is the process ID.

        • Verify that the device name is removed. 

          $ dmsetup ls
          Copy to Clipboard

  8. Delete the ocs-osd-removal job. 

    $ oc delete -n openshift-storage job ocs-osd-removal-job
    Copy to Clipboard

    Example output: 

    job.batch "ocs-osd-removal-job" deleted
    Copy to Clipboard
Note

When using an external key management system (KMS) with data encryption, the old OSD encryption key can be removed from the Vault server as it is now an orphan key.

Verfication steps

  1. Verify that there is a new OSD running. 

    $ oc get -n openshift-storage pods -l app=rook-ceph-osd
    Copy to Clipboard

    Example output: 

    rook-ceph-osd-0-5f7f4747d4-snshw                                  1/1     Running     0          4m47s
rook-ceph-osd-1-85d99fb95f-2svc7                                  1/1     Running     0          1d20h
rook-ceph-osd-2-6c66cdb977-jp542                                  1/1     Running     0          1d20h
    Copy to Clipboard

  2. Verify that there is a new PVC created which is in Bound state. 

    $ oc get -n openshift-storage pvc
    Copy to Clipboard

  3. Optional: If cluster-wide encryption is enabled on the cluster, verify that the new OSD devices are encrypted.

    1. Identify the nodes where the new OSD pods are running. 

      $ oc get -n openshift-storage -o=custom-columns=NODE:.spec.nodeName pod/<OSD-pod-name>
      Copy to Clipboard
      <OSD-pod-name>

      Is the name of the OSD pod.

      For example: 

      $ oc get -n openshift-storage -o=custom-columns=NODE:.spec.nodeName pod/rook-ceph-osd-0-544db49d7f-qrgqm
      Copy to Clipboard

      Example output: 

      NODE
compute-1
      Copy to Clipboard

    2. For each of the previously identified nodes, do the following:

      1. Create a debug pod and open a chroot environment for the selected host(s). 

        $ oc debug node/<node name>
        Copy to Clipboard
        <node name>

        Is the name of the node. 

        $ chroot /host
        Copy to Clipboard

      2. Check for the crypt keyword beside the ocs-deviceset name(s). 

        $ lsblk
        Copy to Clipboard
  4. Log in to OpenShift Web Console and view the storage dashboard.

Chapter 4. Dynamically provisioned OpenShift Data Foundation deployed on Microsoft Azure

4.1. Replacing operational or failed storage devices on Azure installer-provisioned infrastructure

When you need to replace a device in a dynamically created storage cluster on an Azure installer-provisioned infrastructure, you must replace the storage node. For information about how to replace nodes, see:

Chapter 5. OpenShift Data Foundation deployed using local storage devices

5.1. Replacing operational or failed storage devices on clusters backed by local storage devices

You can replace an object storage device (OSD) in OpenShift Data Foundation deployed using local storage devices on the following infrastructures:

  • Bare metal
  • VMware
  • Red Hat Virtualization
Note

One or more underlying storage devices may need to be replaced.

Prerequisites

  • Red Hat recommends that replacement devices are configured with similar infrastructure and resources to the device being replaced.

  • Ensure that the data is resilient.

    • In the OpenShift Web Console, click Storage → Data Foundation.
    • Click the Storage Systems tab, and then click ocs-storagecluster-storagesystem.
    • In the Status card of Block and File dashboard, under the Overview tab, verify that Data Resiliency has a green tick mark.

Procedure

  1. Remove the underlying storage device from relevant worker node.

  2. Verify that relevant OSD Pod has moved to CrashLoopBackOff state.

    Identify the OSD that needs to be replaced and the OpenShift Container Platform node that has the OSD scheduled on it. 

    $ oc get -n openshift-storage pods -l app=rook-ceph-osd -o wide
    Copy to Clipboard

    Example output: 

    rook-ceph-osd-0-6d77d6c7c6-m8xj6    0/1    CrashLoopBackOff    0    24h   10.129.0.16   compute-2   <none>           <none>
rook-ceph-osd-1-85d99fb95f-2svc7    1/1    Running             0    24h   10.128.2.24   compute-0   <none>           <none>
rook-ceph-osd-2-6c66cdb977-jp542    1/1    Running             0    24h   10.130.0.18   compute-1   <none>           <none>
    Copy to Clipboard

    In this example, rook-ceph-osd-0-6d77d6c7c6-m8xj6 needs to be replaced and compute-2 is the OpenShift Container platform node on which the OSD is scheduled.

  3. Scale down the OSD deployment for the OSD to be replaced. 

    $ osd_id_to_remove=0
    Copy to Clipboard 
    $ oc scale -n openshift-storage deployment rook-ceph-osd-${osd_id_to_remove} --replicas=0
    Copy to Clipboard

    where, osd_id_to_remove is the integer in the pod name immediately after the rook-ceph-osd prefix. In this example, the deployment name is rook-ceph-osd-0.

    Example output: 

    deployment.extensions/rook-ceph-osd-0 scaled
    Copy to Clipboard

  4. Verify that the rook-ceph-osd pod is terminated. 

    $ oc get -n openshift-storage pods -l ceph-osd-id=${osd_id_to_remove}
    Copy to Clipboard

    Example output: 

    No resources found in openshift-storage namespace.
    Copy to Clipboard
    Important

    If the rook-ceph-osd pod is in terminating state for more than a few minutes, use the force option to delete the pod. 

    $ oc delete -n openshift-storage pod rook-ceph-osd-0-6d77d6c7c6-m8xj6 --grace-period=0 --force
    Copy to Clipboard

    Example output: 

    warning: Immediate deletion does not wait for confirmation that the running resource has been terminated. The resource may continue to run on the cluster indefinitely.
  pod "rook-ceph-osd-0-6d77d6c7c6-m8xj6" force deleted
    Copy to Clipboard

  5. Remove the old OSD from the cluster so that you can add a new OSD.

    1. Delete any old ocs-osd-removal jobs. 

      $ oc delete -n openshift-storage job ocs-osd-removal-job
      Copy to Clipboard

      Example output: 

      job.batch "ocs-osd-removal-job" deleted
      Copy to Clipboard

    2. Navigate to the openshift-storage project. 

      $ oc project openshift-storage
      Copy to Clipboard

    3. Remove the old OSD from the cluster. 

      $ oc process -n openshift-storage ocs-osd-removal -p FAILED_OSD_IDS=${osd_id_to_remove} -p FORCE_OSD_REMOVAL=false |oc create -n openshift-storage -f -
      Copy to Clipboard

      The FORCE_OSD_REMOVAL value must be changed to “true” in clusters that only have three OSDs, or clusters with insufficient space to restore all three replicas of the data after the OSD is removed.

      Warning

      This step results in OSD being completely removed from the cluster. Ensure that the correct value of osd_id_to_remove is provided.

  6. Verify that the OSD was removed successfully by checking the status of the ocs-osd-removal-job pod.

    A status of Completed confirms that the OSD removal job succeeded. 

    $ oc get pod -l job-name=ocs-osd-removal-job -n openshift-storage
    Copy to Clipboard

  7. Ensure that the OSD removal is completed. 

    $ oc logs -l job-name=ocs-osd-removal-job -n openshift-storage --tail=-1 | egrep -i 'completed removal'
    Copy to Clipboard

    Example output: 

    2022-05-10 06:50:04.501511 I | cephosd: completed removal of OSD 0
    Copy to Clipboard
    Important

    If the ocs-osd-removal-job fails and the pod is not in the expected Completed state, check the pod logs for further debugging.

    For example: 

    # oc logs -l job-name=ocs-osd-removal-job -n openshift-storage --tail=-1
    Copy to Clipboard

  8. If encryption was enabled at the time of install, remove dm-crypt managed device-mapper mapping from the OSD devices that are removed from the respective OpenShift Data Foundation nodes.

    1. Get the Persistent Volume Claim (PVC) name(s) of the replaced OSD(s) from the logs of ocs-osd-removal-job pod. 

      $ oc logs -l job-name=ocs-osd-removal-job -n openshift-storage --tail=-1  |egrep -i 'pvc|deviceset'
      Copy to Clipboard

      Example output: 

      2021-05-12 14:31:34.666000 I | cephosd: removing the OSD PVC "ocs-deviceset-xxxx-xxx-xxx-xxx"
      Copy to Clipboard

    2. For each of the previously identified nodes, do the following:

      1. Create a debug pod and chroot to the host on the storage node. 

        $ oc debug node/<node name>
        Copy to Clipboard
        <node name>

        Is the name of the node. 

        $ chroot /host
        Copy to Clipboard

      2. Find the relevant device name based on the PVC names identified in the previous step. 

        $ dmsetup ls| grep <pvc name>
        Copy to Clipboard
        <pvc name>

        Is the name of the PVC.

        Example output: 

        ocs-deviceset-xxx-xxx-xxx-xxx-block-dmcrypt (253:0)
        Copy to Clipboard

      3. Remove the mapped device. 

        $ cryptsetup luksClose --debug --verbose <ocs-deviceset-name>
        Copy to Clipboard
        <ocs-deviceset-name>

        Is the name of the relevant device based on the PVC names identified in the previous step.

        Important

        If the above command gets stuck due to insufficient privileges, run the following commands:

        • Press CTRL+Z to exit the above command.

        • Find the PID of the process which was stuck. 

          $ ps -ef | grep crypt
          Copy to Clipboard

        • Terminate the process using the kill command. 

          $ kill -9 <PID>
          Copy to Clipboard
          <PID>
          Is the process ID.

        • Verify that the device name is removed. 

          $ dmsetup ls
          Copy to Clipboard

  9. Find the persistent volume (PV) that need to be deleted. 

    $ oc get pv -L kubernetes.io/hostname | grep <storageclass-name> | grep Released
    Copy to Clipboard

    Example output: 

    local-pv-d6bf175b           1490Gi       RWO         Delete          Released            openshift-storage/ocs-deviceset-0-data-0-6c5pw      localblock      2d22h       compute-1
    Copy to Clipboard

  10. Delete the PV. 

    $ oc delete pv <pv_name>
    Copy to Clipboard
  11. Physically add a new device to the node.

  12. Track the provisioning of PVs for the devices that match the deviceInclusionSpec. It can take a few minutes to provision the PVs. 

    $ oc -n openshift-local-storage describe localvolumeset localblock
    Copy to Clipboard

    Example output: 

    [...]
Status:
  Conditions:
    Last Transition Time:          2020-11-17T05:03:32Z
    Message:                       DiskMaker: Available, LocalProvisioner: Available
    Status:                        True
    Type:                          DaemonSetsAvailable
    Last Transition Time:          2020-11-17T05:03:34Z
    Message:                       Operator reconciled successfully.
    Status:                        True
    Type:                          Available
  Observed Generation:             1
  Total Provisioned Device Count: 4
Events:
Type    Reason      Age          From                Message
----    ------      ----         ----                -------
Normal  Discovered  2m30s (x4    localvolumeset-     node.example.com -
        NewDevice   over 2m30s)  symlink-controller  found possible
                                                     matching disk,
                                                     waiting 1m to claim

Normal  FoundMatch  89s (x4      localvolumeset-     node.example.com -
        ingDisk     over 89s)    symlink-controller  symlinking matching
                                                     disk
    Copy to Clipboard

    Once the PV is provisioned, a new OSD pod is automatically created for the PV.

  13. Delete the ocs-osd-removal job(s). 

    $ oc delete -n openshift-storage job ocs-osd-removal-job
    Copy to Clipboard

    Example output: 

    job.batch "ocs-osd-removal-job" deleted
    Copy to Clipboard
Note

When using an external key management system (KMS) with data encryption, the old OSD encryption key can be removed from the Vault server as it is now an orphan key.

Verification steps

  1. Verify that there is a new OSD running. 

    $ oc get -n openshift-storage pods -l app=rook-ceph-osd
    Copy to Clipboard

    Example output: 

    rook-ceph-osd-0-5f7f4747d4-snshw    1/1     Running     0          4m47s
rook-ceph-osd-1-85d99fb95f-2svc7    1/1     Running     0          1d20h
rook-ceph-osd-2-6c66cdb977-jp542    1/1     Running     0          1d20h
    Copy to Clipboard
    Important

    If the new OSD does not show as Running after a few minutes, restart the rook-ceph-operator pod to force a reconciliation. 

    $ oc delete pod -n openshift-storage -l app=rook-ceph-operator
    Copy to Clipboard

    Example output: 

    pod "rook-ceph-operator-6f74fb5bff-2d982" deleted
    Copy to Clipboard

  2. Verify that a new PVC is created. 

    $ oc get -n openshift-storage pvc | grep localblock
    Copy to Clipboard

    Example output: 

    ocs-deviceset-0-0-c2mqb   Bound    local-pv-b481410         1490Gi     RWO            localblock                    5m
ocs-deviceset-1-0-959rp   Bound    local-pv-414755e0        1490Gi     RWO            localblock                    1d20h
ocs-deviceset-2-0-79j94   Bound    local-pv-3e8964d3        1490Gi     RWO            localblock                    1d20h
    Copy to Clipboard

  3. Optional: If cluster-wide encryption is enabled on the cluster, verify that the new OSD devices are encrypted.

    1. Identify the nodes where the new OSD pods are running. 

      $ oc get -n openshift-storage -o=custom-columns=NODE:.spec.nodeName pod/<OSD-pod-name>
      Copy to Clipboard
      <OSD-pod-name>

      Is the name of the OSD pod.

      For example: 

      $ oc get -n openshift-storage -o=custom-columns=NODE:.spec.nodeName pod/rook-ceph-osd-0-544db49d7f-qrgqm
      Copy to Clipboard

      Example output: 

      NODE
compute-1
      Copy to Clipboard

    2. For each of the nodes identified in the previous step, do the following:

      1. Create a debug pod and open a chroot environment for the selected host(s). 

        $ oc debug node/<node name>
        Copy to Clipboard
        <node name>

        Is the name of the node. 

        $ chroot /host
        Copy to Clipboard

      2. Check for the crypt keyword beside the ocs-deviceset name(s). 

        $ lsblk
        Copy to Clipboard
  4. Log in to OpenShift Web Console and check the OSD status on the storage dashboard.
Note

A full data recovery may take longer depending on the volume of data being recovered.

5.2. Replacing operational or failed storage devices on IBM Power

You can replace an object storage device (OSD) in OpenShift Data Foundation deployed using local storage devices on IBM Power.

Note

One or more underlying storage devices may need to be replaced.

Prerequisites

  • Red Hat recommends that replacement devices are configured with similar infrastructure and resources to the device being replaced.

  • Ensure that the data is resilient.

    • In the OpenShift Web Console, click Storage → Data Foundation.
    • Click the Storage Systems tab, and then click ocs-storagecluster-storagesystem.
    • In the Status card of Block and File dashboard, under the Overview tab, verify that Data Resiliency has a green tick mark.

Procedure

  1. Identify the OSD that needs to be replaced and the OpenShift Container Platform node that has the OSD scheduled on it. 

    $ oc get -n openshift-storage pods -l app=rook-ceph-osd -o wide
    Copy to Clipboard

    Example output: 

    rook-ceph-osd-0-86bf8cdc8-4nb5t   0/1     crashLoopBackOff   0   24h   10.129.2.26     worker-0     <none>       <none>
rook-ceph-osd-1-7c99657cfb-jdzvz   1/1     Running   0          24h     10.128.2.46     worker-1     <none>       <none>
rook-ceph-osd-2-5f9f6dfb5b-2mnw9    1/1     Running   0          24h     10.131.0.33    worker-2     <none>       <none>
    Copy to Clipboard

    In this example, rook-ceph-osd-0-86bf8cdc8-4nb5t needs to be replaced and worker-0 is the RHOCP node on which the OSD is scheduled.

    Note

    If the OSD to be replaced is healthy, the status of the pod will be Running.

  2. Scale down the OSD deployment for the OSD to be replaced. 

    $ osd_id_to_remove=0
    Copy to Clipboard 
    $ oc scale -n openshift-storage deployment rook-ceph-osd-${osd_id_to_remove} --replicas=0
    Copy to Clipboard

    where, osd_id_to_remove is the integer in the pod name immediately after the rook-ceph-osd prefix. In this example, the deployment name is rook-ceph-osd-0.

    Example output: 

    deployment.extensions/rook-ceph-osd-0 scaled
    Copy to Clipboard

  3. Verify that the rook-ceph-osd pod is terminated. 

    $ oc get -n openshift-storage pods -l ceph-osd-id=${osd_id_to_remove}
    Copy to Clipboard

    Example output: 

    No resources found in openshift-storage namespace.
    Copy to Clipboard
    Important

    If the rook-ceph-osd pod is in terminating state for more than a few minutes, use the force option to delete the pod. 

    $ oc delete -n openshift-storage pod rook-ceph-osd-0-86bf8cdc8-4nb5t --grace-period=0 --force
    Copy to Clipboard

    Example output: 

    warning: Immediate deletion does not wait for confirmation that the running resource has been terminated. The resource may continue to run on the cluster indefinitely.
  pod "rook-ceph-osd-0-86bf8cdc8-4nb5t" force deleted
    Copy to Clipboard

  4. Remove the old OSD from the cluster so that you can add a new OSD.

    1. Identify the DeviceSet associated with the OSD to be replaced. 

      $ oc get -n openshift-storage -o yaml deployment rook-ceph-osd-${osd_id_to_remove} | grep ceph.rook.io/pvc
      Copy to Clipboard

      Example output: 

      ceph.rook.io/pvc: ocs-deviceset-localblock-0-data-0-64xjl
    ceph.rook.io/pvc: ocs-deviceset-localblock-0-data-0-64xjl
      Copy to Clipboard

      In this example, the Persistent Volume Claim (PVC) name is ocs-deviceset-localblock-0-data-0-64xjl.

    2. Identify the Persistent Volume (PV) associated with the PVC. 

      $ oc get -n openshift-storage pvc ocs-deviceset-<x>-<y>-<pvc-suffix>
      Copy to Clipboard

      where, x, y, and pvc-suffix are the values in the DeviceSet identified in an earlier step.

      Example output: 

      NAME                      STATUS        VOLUME        CAPACITY   ACCESS MODES   STORAGECLASS   AGE
ocs-deviceset-localblock-0-data-0-64xjl   Bound    local-pv-8137c873    256Gi      RWO     localblock     24h
      Copy to Clipboard

      In this example, the associated PV is local-pv-8137c873.

    3. Identify the name of the device to be replaced. 

      $ oc get pv local-pv-<pv-suffix> -o yaml | grep path
      Copy to Clipboard

      where, pv-suffix is the value in the PV name identified in an earlier step.

      Example output: 

      path: /mnt/local-storage/localblock/vdc
      Copy to Clipboard

      In this example, the device name is vdc.

    4. Identify the prepare-pod associated with the OSD to be replaced. 

      $ oc describe -n openshift-storage pvc ocs-deviceset-<x>-<y>-<pvc-suffix> | grep Used
      Copy to Clipboard

      where, x, y, and pvc-suffix are the values in the DeviceSet identified in an earlier step.

      Example output: 

      Used By:    rook-ceph-osd-prepare-ocs-deviceset-localblock-0-data-0-64knzkc
      Copy to Clipboard

      In this example, the prepare-pod name is rook-ceph-osd-prepare-ocs-deviceset-localblock-0-data-0-64knzkc.

    5. Delete any old ocs-osd-removal jobs. 

      $ oc delete -n openshift-storage job ocs-osd-removal-job
      Copy to Clipboard

      Example output: 

      job.batch "ocs-osd-removal-job" deleted
      Copy to Clipboard

    6. Change to the openshift-storage project. 

      $ oc project openshift-storage
      Copy to Clipboard

    7. Remove the old OSD from the cluster. 

      $ oc process -n openshift-storage ocs-osd-removal -p FAILED_OSD_IDS=${osd_id_to_remove} -p FORCE_OSD_REMOVAL=false |oc create -n openshift-storage -f -
      Copy to Clipboard

      The FORCE_OSD_REMOVAL value must be changed to “true” in clusters that only have three OSDs, or clusters with insufficient space to restore all three replicas of the data after the OSD is removed.

      Warning

      This step results in OSD being completely removed from the cluster. Ensure that the correct value of osd_id_to_remove is provided.

  5. Verify that the OSD was removed successfully by checking the status of the ocs-osd-removal-job pod.

    A status of Completed confirms that the OSD removal job succeeded. 

    $ oc get pod -l job-name=ocs-osd-removal-job -n openshift-storage
    Copy to Clipboard

  6. Ensure that the OSD removal is completed. 

    $ oc logs -l job-name=ocs-osd-removal-job -n openshift-storage --tail=-1 | egrep -i 'completed removal'
    Copy to Clipboard

    Example output: 

    2022-05-10 06:50:04.501511 I | cephosd: completed removal of OSD 0
    Copy to Clipboard
    Important

    If the ocs-osd-removal-job fails and the pod is not in the expected Completed state, check the pod logs for further debugging.

    For example: 

    # oc logs -l job-name=ocs-osd-removal-job -n openshift-storage --tail=-1
    Copy to Clipboard

  7. If encryption was enabled at the time of install, remove dm-crypt managed device-mapper mapping from the OSD devices that are removed from the respective OpenShift Data Foundation nodes.

    1. Get the PVC name(s) of the replaced OSD(s) from the logs of ocs-osd-removal-job pod. 

      $ oc logs -l job-name=ocs-osd-removal-job -n openshift-storage --tail=-1  |egrep -i ‘pvc|deviceset’
      Copy to Clipboard

      Example output: 

      2021-05-12 14:31:34.666000 I | cephosd: removing the OSD PVC "ocs-deviceset-xxxx-xxx-xxx-xxx"
      Copy to Clipboard

    2. For each of the previously identified nodes, do the following:

      1. Create a debug pod and chroot to the host on the storage node. 

        $ oc debug node/<node name>
        Copy to Clipboard
        <node name>

        Is the name of the node. 

        $ chroot /host
        Copy to Clipboard

      2. Find the relevant device name based on the PVC names identified in the previous step. 

        $ dmsetup ls| grep <pvc name>
        Copy to Clipboard
        <pvc name>

        Is the name of the PVC.

        Example output: 

        ocs-deviceset-xxx-xxx-xxx-xxx-block-dmcrypt (253:0)
        Copy to Clipboard

      3. Remove the mapped device. 

        $ cryptsetup luksClose --debug --verbose ocs-deviceset-xxx-xxx-xxx-xxx-block-dmcrypt
        Copy to Clipboard
        Important

        If the above command gets stuck due to insufficient privileges, run the following commands:

        • Press CTRL+Z to exit the above command.

        • Find the PID of the process which was stuck. 

          $ ps -ef | grep crypt
          Copy to Clipboard

        • Terminate the process using the kill command. 

          $ kill -9 <PID>
          Copy to Clipboard
          <PID>
          Is the process ID.

        • Verify that the device name is removed. 

          $ dmsetup ls
          Copy to Clipboard

  8. Find the PV that need to be deleted. 

    $ oc get pv -L kubernetes.io/hostname | grep localblock | grep Released
    Copy to Clipboard

    Example output: 

    local-pv-d6bf175b           1490Gi       RWO         Delete          Released            openshift-storage/ocs-deviceset-0-data-0-6c5pw      localblock      2d22h       compute-1
    Copy to Clipboard

  9. Delete the PV. 

    $ oc delete pv <pv-name>
    Copy to Clipboard
    <pv-name>
    Is the name of the PV.

  10. Replace the old device and use the new device to create a new OpenShift Container Platform PV.

    1. Log in to the OpenShift Container Platform node with the device to be replaced. In this example, the OpenShift Container Platform node is worker-0. 

      $ oc debug node/worker-0
      Copy to Clipboard

      Example output: 

      Starting pod/worker-0-debug ...
To use host binaries, run `chroot /host`
Pod IP: 192.168.88.21
If you don't see a command prompt, try pressing enter.
# chroot /host
      Copy to Clipboard

    2. Record the /dev/disk that is to be replaced using the device name, vdc, identified earlier. 

      # ls -alh /mnt/local-storage/localblock
      Copy to Clipboard

      Example output: 

      total 0
drwxr-xr-x. 2 root root 17 Nov  18 15:23 .
drwxr-xr-x. 3 root root 24 Nov  18 15:23 ..
lrwxrwxrwx. 1 root root  8 Nov  18 15:23 vdc -> /dev/vdc
      Copy to Clipboard

    3. Find the name of the LocalVolume CR, and remove or comment out the device /dev/disk that is to be replaced. 

      $ oc get -n openshift-local-storage localvolume
      Copy to Clipboard

      Example output: 

      NAME          AGE
localblock   25h
      Copy to Clipboard 
      # oc edit -n openshift-local-storage localvolume localblock
      Copy to Clipboard

      Example output: 

      [...]
    storageClassDevices:
    - devicePaths:
   #   - /dev/vdc
      storageClassName: localblock
      volumeMode: Block
[...]
      Copy to Clipboard

      Make sure to save the changes after editing the CR.

  11. Log in to the OpenShift Container Platform node with the device to be replaced and remove the old symlink. 

    $ oc debug node/worker-0
    Copy to Clipboard

    Example output: 

    Starting pod/worker-0-debug ...
To use host binaries, run `chroot /host`
Pod IP: 192.168.88.21
If you don't see a command prompt, try pressing enter.
# chroot /host
    Copy to Clipboard

    1. Identify the old symlink for the device name to be replaced. In this example, the device name is vdc. 

      # ls -alh /mnt/local-storage/localblock
      Copy to Clipboard

      Example output: 

      total 0
drwxr-xr-x. 2 root root 17 Nov  18 15:23 .
drwxr-xr-x. 3 root root 24 Nov  18 15:23 ..
lrwxrwxrwx. 1 root root  8 Nov  18 15:23 vdc -> /dev/vdc
      Copy to Clipboard

    2. Remove the symlink. 

      # rm /mnt/local-storage/localblock/vdc
      Copy to Clipboard

    3. Verify that the symlink is removed. 

      # ls -alh /mnt/local-storage/localblock
      Copy to Clipboard

      Example output: 

      total 0
drwxr-xr-x. 2 root root 6 Nov 18 17:11 .
drwxr-xr-x. 3 root root 24 Nov 18 15:23 ..
      Copy to Clipboard
  12. Replace the old device with the new device.

  13. Log back into the correct OpenShift Cotainer Platform node and identify the device name for the new drive. The device name must change unless you are resetting the same device. 

    # lsblk
    Copy to Clipboard

    Example output: 

    NAME                         MAJ:MIN RM   SIZE RO TYPE MOUNTPOINT
vda                          252:0    0   40G  0 disk
|-vda1                       252:1    0    4M  0 part
|-vda2                       252:2    0  384M  0 part /boot
`-vda4                       252:4    0 39.6G  0 part
  `-coreos-luks-root-nocrypt 253:0    0 39.6G  0 dm   /sysroot
vdb                          252:16   0  512B  1 disk
vdd                          252:32   0  256G  0 disk
    Copy to Clipboard

    In this example, the new device name is vdd.

  14. After the new /dev/disk is available, you can add a new disk entry to the LocalVolume CR.

    1. Edit the LocalVolume CR and add the new /dev/disk.

      In this example, the new device is /dev/vdd. 

      # oc edit -n openshift-local-storage localvolume localblock
      Copy to Clipboard

      Example output: 

      [...]
    storageClassDevices:
    - devicePaths:
    #  - /dev/vdc
      - /dev/vdd
      storageClassName: localblock
      volumeMode: Block
[...]
      Copy to Clipboard

      Make sure to save the changes after editing the CR.

  15. Verify that there is a new PV in Available state and of the correct size. 

    $ oc get pv | grep 256Gi
    Copy to Clipboard

    Example output: 

    local-pv-1e31f771   256Gi   RWO    Delete  Bound  openshift-storage/ocs-deviceset-localblock-2-data-0-6xhkf   localblock    24h
local-pv-ec7f2b80   256Gi   RWO    Delete  Bound  openshift-storage/ocs-deviceset-localblock-1-data-0-hr2fx   localblock    24h
local-pv-8137c873   256Gi   RWO    Delete  Available                                                          localblock    32m
    Copy to Clipboard

  16. Create a new OSD for the new device.

    Deploy the new OSD. You need to restart the rook-ceph-operator to force operator reconciliation.

    1. Identify the name of the rook-ceph-operator. 

      $ oc get -n openshift-storage pod -l app=rook-ceph-operator
      Copy to Clipboard

      Example output: 

      NAME                                  READY   STATUS    RESTARTS   AGE
rook-ceph-operator-85f6494db4-sg62v   1/1     Running   0          1d20h
      Copy to Clipboard

    2. Delete the rook-ceph-operator. 

      $ oc delete -n openshift-storage pod rook-ceph-operator-85f6494db4-sg62v
      Copy to Clipboard

      Example output: 

      pod "rook-ceph-operator-85f6494db4-sg62v" deleted
      Copy to Clipboard

      In this example, the rook-ceph-operator pod name is rook-ceph-operator-85f6494db4-sg62v.

    3. Verify that the rook-ceph-operator pod is restarted. 

      $ oc get -n openshift-storage pod -l app=rook-ceph-operator
      Copy to Clipboard

      Example output: 

      NAME                                  READY   STATUS    RESTARTS   AGE
rook-ceph-operator-85f6494db4-wx9xx   1/1     Running   0          50s
      Copy to Clipboard

      Creation of the new OSD may take several minutes after the operator restarts.

  17. Delete the ocs-osd-removal job(s). 

    $ oc delete -n openshift-storage job ocs-osd-removal-job
    Copy to Clipboard

    Example output: 

    job.batch "ocs-osd-removal-job" deleted
    Copy to Clipboard
Note

When using an external key management system (KMS) with data encryption, the old OSD encryption key can be removed from the Vault server as it is now an orphan key.

Verfication steps

  1. Verify that there is a new OSD running. 

    $ oc get -n openshift-storage pods -l app=rook-ceph-osd
    Copy to Clipboard

    Example output: 

    rook-ceph-osd-0-76d8fb97f9-mn8qz   1/1     Running   0          23m
rook-ceph-osd-1-7c99657cfb-jdzvz   1/1     Running   1          25h
rook-ceph-osd-2-5f9f6dfb5b-2mnw9   1/1     Running   0          25h
    Copy to Clipboard

  2. Verify that a new PVC is created. 

    $ oc get -n openshift-storage pvc | grep localblock
    Copy to Clipboard

    Example output: 

    ocs-deviceset-localblock-0-data-0-q4q6b   Bound    local-pv-8137c873       256Gi     RWO         localblock         10m
ocs-deviceset-localblock-1-data-0-hr2fx   Bound    local-pv-ec7f2b80       256Gi     RWO         localblock         1d20h
ocs-deviceset-localblock-2-data-0-6xhkf   Bound    local-pv-1e31f771       256Gi     RWO         localblock         1d20h
    Copy to Clipboard

  3. Optional: If cluster-wide encryption is enabled on the cluster, verify that the new OSD devices are encrypted.

    1. Identify the nodes where the new OSD pods are running. 

      $ oc get -n openshift-storage -o=custom-columns=NODE:.spec.nodeName pod/<OSD-pod-name>
      Copy to Clipboard
      <OSD-pod-name>

      Is the name of the OSD pod.

      For example: 

      $ oc get -n openshift-storage -o=custom-columns=NODE:.spec.nodeName pod/rook-ceph-osd-0-544db49d7f-qrgqm
      Copy to Clipboard

      Example output: 

      NODE
compute-1
      Copy to Clipboard

    2. For each of the previously identified nodes, do the following:

      1. Create a debug pod and open a chroot environment for the selected host(s). 

        $ oc debug node/<node name>
        Copy to Clipboard
        <node name>

        Is the name of the node. 

        $ chroot /host
        Copy to Clipboard

      2. Check for the crypt keyword beside the ocs-deviceset name(s). 

        $ lsblk
        Copy to Clipboard
  4. Log in to OpenShift Web Console and check the status card in the OpenShift Data Foundation dashboard under Storage section.
Note

A full data recovery may take longer depending on the volume of data being recovered.

5.3. Replacing operational or failed storage devices on IBM Z or LinuxONE infrastructure

You can replace operational or failed storage devices on IBM Z or LinuxONE infrastructure with new Small Computer System Interface (SCSI) disks.

IBM Z or LinuxONE supports SCSI FCP disk logical units (SCSI disks) as persistent storage devices from external disk storage. You can identify a SCSI disk using its FCP Device number, two target worldwide port names (WWPN1 and WWPN2), and the logical unit number (LUN). For more information, see https://www.ibm.com/support/knowledgecenter/SSB27U_6.4.0/com.ibm.zvm.v640.hcpa5/scsiover.html

Prerequisites

  • Ensure that the data is resilient.

    • In the OpenShift Web Console, click Storage → Data Foundation.
    • Click the Storage Systems tab, and then click ocs-storagecluster-storagesystem.
    • In the Status card of Block and File dashboard, under the Overview tab, verify that Data Resiliency has a green tick mark.

Procedure

  1. List all the disks. 

    $ lszdev
    Copy to Clipboard

    Example output: 

    TYPE         ID
zfcp-host    0.0.8204                                        yes  yes
zfcp-lun     0.0.8204:0x102107630b1b5060:0x4001402900000000 yes  no    sda sg0
zfcp-lun     0.0.8204:0x500407630c0b50a4:0x3002b03000000000  yes  yes   sdb sg1
qeth         0.0.bdd0:0.0.bdd1:0.0.bdd2                      yes  no    encbdd0
generic-ccw  0.0.0009                                        yes  no
    Copy to Clipboard

    A SCSI disk is represented as a zfcp-lun with the structure <device-id>:<wwpn>:<lun-id> in the ID section. The first disk is used for the operating system. If one storage device fails, you can replace it with a new disk.

  2. Remove the disk.

    Run the following command on the disk, replacing scsi-id with the SCSI disk identifier of the disk to be replaced: 

    $ chzdev -d scsi-id
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    For example, the following command removes one disk with the device ID 0.0.8204, the WWPN 0x500507630a0b50a4, and the LUN 0x4002403000000000: 

    $ chzdev -d 0.0.8204:0x500407630c0b50a4:0x3002b03000000000
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  3. Append a new SCSI disk. 

    $ chzdev -e 0.0.8204:0x500507630b1b50a4:0x4001302a00000000
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    Note

    The device ID for the new disk must be the same as the disk to be replaced. The new disk is identified with its WWPN and LUN ID.

  4. List all the FCP devices to verify the new disk is configured. 

    $ lszdev zfcp-lun
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    Example output: 

    TYPE         ID                                              ON   PERS  NAMES
zfcp-lun     0.0.8204:0x102107630b1b5060:0x4001402900000000 yes  no    sda sg0
zfcp-lun     0.0.8204:0x500507630b1b50a4:0x4001302a00000000  yes  yes   sdb sg1
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