Replacing devices

Red Hat OpenShift Container Storage 4.6

Instructions for safely replacing failed devices

Red Hat Storage Documentation Team

Abstract

This document explains how to safely replace storage devices for Red Hat OpenShift Container Storage.

Preface

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

For dynamically created storage clusters deployed on AWS, see:
- Section 1.1, “Replacing operational or failed storage devices on AWS user-provisioned infrastructure”
- Section 1.2, “Replacing operational or failed storage devices on AWS installer-provisioned infrastructure”
For dynamically created storage clusters deployed on VMware, see Section 2.1, “Replacing operational or failed storage devices on VMware user-provisioned infrastructure”
For dynamically created storage clusters deployed on Microsoft Azure, see Section 3.1, “Replacing operational or failed storage devices on Azure installer-provisioned infrastructure”
For storage clusters deployed using local storage devices, see:

Note

OpenShift Container Storage does not support heterogeneous OSD sizes.

Chapter 1. Dynamically provisioned OpenShift Container Storage 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 Container Storage deployed on VMware

2.1. Replacing operational or failed storage devices on VMware user-provisioned infrastructure

Use this procedure when one or more virtual machine disks (VMDK) needs to be replaced in OpenShift Container Storage which is deployed dynamically on VMware infrastructure. This procedure helps to create a new Persistent Volume Claim (PVC) on a new volume and remove the old object storage device (OSD).

Procedure

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

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>

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.

Scale down the OSD deployment for the OSD to be replaced.
```
# osd_id_to_remove=0
# oc scale -n openshift-storage deployment rook-ceph-osd-${osd_id_to_remove} --replicas=0
```
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
```

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

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

Example output:

No resources found.

Note

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

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

Remove the old OSD from the cluster so that a new OSD can be added.
1. Delete any old ocs-osd-removal jobs.
```
$ oc delete -n openshift-storage job ocs-osd-removal-${osd_id_to_remove}
```
  Example output:
```
job.batch "ocs-osd-removal-0" deleted
```
2. Change to the openshift-storage project.
```
$ oc project openshift-storage
```
3. Remove the old OSD from the cluster.
```
$ oc process -n openshift-storage ocs-osd-removal -p FAILED_OSD_IDS=${osd_id_to_remove} |oc create -n openshift-storage -f -
```
  Warning
  This step results in OSD being completely removed from the cluster. Ensure that the correct value of osd_id_to_remove is provided.
Verify that the OSD is removed successfully by checking the status of the ocs-osd-removal pod. A status of Completed confirms that the OSD removal job succeeded.
```
# oc get pod -l job-name=ocs-osd-removal-${osd_id_to_remove} -n openshift-storage
```
Note
If ocs-osd-removal 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-${osd_id_to_remove} -n openshift-storage --tail=-1
```
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 Container Storage nodes.
1. Get 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’
```
  For example:
```
2021-05-12 14:31:34.666000 I | cephosd: removing the OSD PVC "ocs-deviceset-xxxx-xxx-xxx-xxx"
```
2. For each of the nodes identified in step #1, do the following:
  1. Create a debug pod and chroot to the host on the storage node.
    $ oc debug node/<node name> $ chroot /host
  2. Find relevant device name based on the PVC names identified in the previous step
    sh-4.4# dmsetup ls| grep <pvc name> ocs-deviceset-xxx-xxx-xxx-xxx-block-dmcrypt (253:0)
  3. Remove the mapped device.
    $ cryptsetup luksClose --debug --verbose ocs-deviceset-xxx-xxx-xxx-xxx-block-dmcrypt
    Note
    If the above command gets stuck due to insufficient privileges, run the following commands:
    Press CTRL+Z to exit the above command.
    Find PID of the process which was stuck.
    $ ps -ef | grep crypt
    Terminate the process using kill command.
    $ kill -9 <PID>
    Verify that the device name is removed.
    $ dmsetup ls

Delete the ocs-osd-removal job.

# oc delete -n openshift-storage job ocs-osd-removal-${osd_id_to_remove}

Example output:

job.batch "ocs-osd-removal-0" deleted

Verfication steps

Verify that there is a new OSD running.

# oc get -n openshift-storage pods -l app=rook-ceph-osd

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

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

# oc get -n openshift-storage pvc

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

(Optional) If data encryption is enabled on the cluster, verify that the new OSD devices are encrypted.
1. Identify the node(s) where the new OSD pod(s) are running.
```
$ oc get -o=custom-columns=NODE:.spec.nodeName pod/<OSD pod name>
```
  For example:
```
oc get -o=custom-columns=NODE:.spec.nodeName pod/rook-ceph-osd-0-544db49d7f-qrgqm
```
2. For each of the nodes identified in 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> $ chroot /host
  2. Run “lsblk” and check for the “crypt” keyword beside the ocs-deviceset name(s)
    $ lsblk
Log in to OpenShift Web Console and view the storage dashboard.
Figure 2.1. OSD status in OpenShift Container Platform storage dashboard after device replacement

Chapter 3. Dynamically provisioned OpenShift Container Storage deployed on Microsoft Azure

3.1. 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 4. OpenShift Container Storage deployed using local storage devices

4.1. Replacing failed storage devices on Amazon EC2 infrastructure

When you need to replace a storage device on an Amazon EC2 (storage-optimized I3) infrastructure, you must replace the storage node. For information about how to replace nodes, see Replacing failed storage nodes on Amazon EC2 infrastructure.

4.2. Replacing failed storage devices on VMware and bare metal infrastructures using user interface

Use this procedure to replace a storage device that has failed due to I/O errors. You can initiate the replacement of a failed storage device from the Cluster or the Persistent Storage dashboards, Nodes page, or the Notifications.

However, if the failure has removed the disk, you need to replace the object storage device (OSD) using the command line steps described in the Replacing operational or failed storage devices on clusters backed by local storage devices section.

Note

For encrypted cluster, replacing a failed device from user interface is not supported. To replace the device from the command-line interface, follow the steps from chapter Replacing operational or failed storage devices on clusters backed by local storage devices section.

Prerequisites

Red Hat recommends that replacement nodes are configured with similar infrastructure, resources, and disks to the node being replaced.
If you upgraded to OpenShift Container Storage 4.6 from a previous version, ensure to add annotations to storage cluster to enable failed device replacement from the user interface. See Adding annotations.
If you upgraded to OpenShift Container Storage 4.6 from a previous version, ensure that you have followed post-upgrade procedures to create the LocalVolumeDiscovery object. See Post-update configuration changes for details.
If you upgraded to OpenShift Container Storage 4.6 from a previous version, ensure that you have followed post-upgrade procedures to create the LocalVolumeSet object. See Post-update configuration changes for details."

Procedure

From the Cluster or Persistent Storage dashboard

Open either the Cluster or the Persistent Storage dashboard.
- Click Home → Overview → Cluster from the left navigation bar of the OpenShift Web Console.
  Figure 4.1. Cluster dashboard with the alert
- Click Home → Overview → Persistent Storage from the left navigation bar of the OpenShift Web Console.
  Figure 4.2. Persistent Storage dashboard with the alert
Click Troubleshoot in the Disk <disk1> not responding or the Disk <disk1> not accessible alert.
Note
In case the disk failure has removed the disk, you might not see the failed disk when you click the link. In such a scenario, you need to perform command line steps as described in the Replacing operational or failed storage devices on clusters backed by local storage devices section.
Figure 4.3. Disks page to replace failed disk
On the Disks page, you can do one of the following:
- Click the here link in the Troubleshoot popover dialog and follow the steps in the Troubleshooting OpenShift Container Storage guide to confirm that the disk has actually failed.
- From the Action (⋮) menu of the failed disk, click Start Disk Replacement.
OpenShift Container Storage Status field of the disk changes to PreparingToReplace. Wait for the OpenShift Container Storage Status field to change to ReplacementReady.
Confirm that the disk alert no longer appears by clicking the notification bell.
Replace the disk and wait for it to appear in the inventory list.
Delete the ocs-osd-removal job for the replaced disk.
1. On the OpenShift Web Console, navigate to Workloads→Jobs.
2. Use the search by Name filter to look for ocs-osd-removal . Ensure that the Project selected is openshift-storage.
3. For the listed job, click the Action (⋮) menu and select Delete Job .
4. Confirm that the job is deleted.
Delete the PersistentVolume resource associated with the replaced disk.
1. On the OpenShift Web Console, navigate to Storage → PersistentVolumes.
2. Use the search by Name filter to look for the PersistentVolume in Released status.
3. For the listed PersistentVolume from the storage class created as part of the LocalVolumeSet creation, for example, localblock, click the Action (⋮) menu and select Delete PersistentVolume.
Verify that the OpenShift Container Storage Status shows Online for the newly added disk.

From the inventory list

Click Compute → Nodes from the OpenShift Web Console.
Figure 4.4. Inventory list of disks in the Nodes page
Click the Disks tab. From the Action (:) menu of the failed disk, click Start Disk Replacement.
OpenShift Container Storage Status field of the disk changes to PreparingToReplace. Wait for the OpenShift Container Storage Status field to change to ReplacementReady.
Confirm that the disk alert no longer appears by clicking the notification bell.
Replace the disk and wait for it to appear in the inventory list.
Delete the ocs-osd-removal job for the replaced disk.
1. On the OpenShift Web Console, navigate to Workloads→Jobs.
2. Use the search by Name filter to look for ocs-osd-removal . Ensure that the Project selected is openshift-storage.
3. For the listed job, click the Action (⋮) menu and select Delete Job .
4. Confirm that the job is deleted.
Delete the PersistentVolume resource associated with the replaced disk.
1. On the OpenShift Web Console, navigate to Storage → PersistentVolumes.
2. Use the search by Name filter to look for the PersistentVolume in Released status.
3. For the listed PersistentVolume from the storage class created as part of the LocalVolumeSet creation, for example, localblock, click the Action (⋮) menu and select Delete PersistentVolume.
Verify that the OpenShift Container Storage Status shows Online for the newly added disk.

From the Notifications

Click Home → Overview → Persistent Storage or Cluster dashboard or click Compute → Nodes → Disks tab.
Look for one of the following alerts in the Notifications of the Cluster or the Persistent Storage dashboard or in the Nodes page:
- CephOSDDiskUnavailable
- CephOSDDiskNotResponding
Click Troubleshoot in the alert notification.
Note
In case the disk failure has removed the disk, you might not see the failed disk when you click the link. In such a scenario, you need to perform command line steps as described in the Replacing operational or failed storage devices on clusters backed by local storage devices section.
Figure 4.5. Notification of disk failure
In the Disks page, you can do one of the following:
- Click the here link in the Troubleshoot popover dialog and follow the steps in the Troubleshooting OpenShift Container Storage guide to confirm that the disk has actually failed.
- From the Action (⋮) menu of the failed disk, click Start Disk Replacement.
OpenShift Container Storage Status of the disk changes to PreparingToReplace and once it is ready to be replaced, the status changes to ReplacementReady.
Confirm that the disk alert no longer appears by clicking the notification bell.
Replace the disk and wait for it to appear in the inventory list.
Delete the ocs-osd-removal job for the replaced disk.
1. On the OpenShift Web Console, navigate to Workloads→Jobs.
2. Use the search by Name filter to look for ocs-osd-removal . Ensure that the Project selected is openshift-storage.
3. For the listed job, click the Action (⋮) menu and select Delete Job .
4. Confirm that the job is deleted.
Delete the PersistentVolume resource associated with the replaced disk.
1. On the OpenShift Web Console, navigate to Storage → PersistentVolumes.
2. Use the search by Name filter to look for the PersistentVolume in Released status.
3. For the listed PersistentVolume from the storage class created as part of the LocalVolumeSet creation, for example, localblock, click the Action (⋮) menu and select Delete PersistentVolume.
Verify that the OpenShift Container Storage Status shows Online for the newly added disk.

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

You can replace an object storage device (OSD) in OpenShift Container Storage deployed using local storage devices on bare metal and VMware infrastructures. Use this procedure when one or more underlying storage devices need to be replaced.

Prerequisites

Red Hat recommends that replacement nodes are configured with similar infrastructure and resources to the node being replaced.
If you upgraded to OpenShift Container Storage 4.6 from a previous version, ensure that you have followed post-upgrade procedures to create the LocalVolumeDiscovery object. See Post-update configuration changes for details.
If you upgraded to OpenShift Container Storage 4.6 from a previous version, ensure that you have followed post-upgrade procedures to create the LocalVolumeSet object. See Post-update configuration changes for details.

Procedure

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

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>

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.

Scale down the OSD deployment for the OSD to be replaced.
```
$ osd_id_to_remove=0
$ oc scale -n openshift-storage deployment rook-ceph-osd-${osd_id_to_remove} --replicas=0
```
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
```

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

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

Example output:

No resources found in openshift-storage namespace.

Note

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

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

Remove the old OSD from the cluster so that a new OSD can be added.
1. Delete any old ocs-osd-removal jobs.
```
$ oc delete -n openshift-storage job ocs-osd-removal-${osd_id_to_remove}
```
  Example output:
```
job.batch "ocs-osd-removal-0" deleted
```
2. Change to the openshift-storage project.
```
$ oc project openshift-storage
```
3. Remove the old OSD from the cluster.
```
$ oc process -n openshift-storage ocs-osd-removal -p FAILED_OSD_IDS=${osd_id_to_remove} |oc create -n openshift-storage -f -
```
  Warning
  This step results in OSD being completely removed from the cluster. Ensure that the correct value of osd_id_to_remove is provided.
Verify that the OSD is removed successfully by checking the status of the ocs-osd-removal pod. A status of Completed confirms that the OSD removal job succeeded.
```
$ oc get pod -l job-name=ocs-osd-removal-${osd_id_to_remove} -n openshift-storage
```
Note
If ocs-osd-removal 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-${osd_id_to_remove} -n openshift-storage --tail=-1
```
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 Container Storage nodes.
1. Get 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’
```
  For example:
```
2021-05-12 14:31:34.666000 I | cephosd: removing the OSD PVC "ocs-deviceset-xxxx-xxx-xxx-xxx"
```
2. For each of the nodes identified in step #1, do the following:
  1. Create a debug pod and chroot to the host on the storage node.
    $ oc debug node/<node name> $ chroot /host
  2. Find relevant device name based on the PVC names identified in the previous step
    sh-4.4# dmsetup ls| grep <pvc name> ocs-deviceset-xxx-xxx-xxx-xxx-block-dmcrypt (253:0)
  3. Remove the mapped device.
    $ cryptsetup luksClose --debug --verbose ocs-deviceset-xxx-xxx-xxx-xxx-block-dmcrypt
    Note
    If the above command gets stuck due to insufficient privileges, run the following commands:
    Press CTRL+Z to exit the above command.
    Find PID of the process which was stuck.
    $ ps -ef | grep crypt
    Terminate the process using kill command.
    $ kill -9 <PID>
    Verify that the device name is removed.
    $ dmsetup ls

Find the persistent volume (PV) that need to be deleted by the command:

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

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

Delete the persistent volume.
```
$ oc delete pv local-pv-d6bf175b
```
Physically add a new device to the node.
You can also remove the old device (optional).

Use the following command to track provisioning of persistent volumes for devices that match the deviceInclusionSpec. It can take a few minutes to provision persistent volumes.

$ oc -n openshift-local-storage describe localvolumeset localblock

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

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

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

$ oc delete -n openshift-storage job ocs-osd-removal-${osd_id_to_remove}

Verfication steps

Verify that there is a new OSD running.

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

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

Note

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

Example output:

pod "rook-ceph-operator-6f74fb5bff-2d982" deleted

Verify that a new PVC is created.

# oc get -n openshift-storage pvc | grep localblock

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

(Optional) If data encryption is enabled on the cluster, verify that the new OSD devices are encrypted.
1. Identify the node(s) where the new OSD pod(s) are running.
```
$ oc get -o=custom-columns=NODE:.spec.nodeName pod/<OSD pod name>
```
  For example:
```
oc get -o=custom-columns=NODE:.spec.nodeName pod/rook-ceph-osd-0-544db49d7f-qrgqm
```
2. For each of the nodes identified in 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> $ chroot /host
  2. Run “lsblk” and check for the “crypt” keyword beside the ocs-deviceset name(s)
    $ lsblk
Log in to OpenShift Web Console and check the OSD status on the storage dashboard.
Figure 4.6. OSD status in OpenShift Container Platform storage dashboard after device replacement

Note

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

4.4. Replacing operational or failed storage devices on IBM Power Systems

You can replace an object storage device (OSD) in OpenShift Container Storage deployed using local storage devices on IBM Power Systems. Use this procedure when an underlying storage device needs to be replaced.

Procedure

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

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>

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.

Scale down the OSD deployment for the OSD to be replaced.
```
# osd_id_to_remove=0
# oc scale -n openshift-storage deployment rook-ceph-osd-${osd_id_to_remove} --replicas=0
```
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.apps/rook-ceph-osd-0 scaled
```

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

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

Example output:

No resources found in openshift-storage namespace.

Note

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

# oc delete pod rook-ceph-osd-0-86bf8cdc8-4nb5t --grace-period=0 --force

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

Remove the old OSD from the cluster so that a new OSD can be added.
1. Identify the DeviceSet associated with the OSD to be replaced.
```
# oc get -n openshift-storage -o yaml deployment rook-ceph-osd-${osd_id_to_remove} | grep ceph.rook.io/pvc
```
  Example output:
```
ceph.rook.io/pvc: ocs-deviceset-localblock-0-data-0-64xjl
    ceph.rook.io/pvc: ocs-deviceset-localblock-0-data-0-64xjl
```
  In this example, the PVC name is ocs-deviceset-localblock-0-data-0-64xjl.
2. Remove the old OSD from the cluster
```
# oc process -n openshift-storage ocs-osd-removal -p FAILED_OSD_IDS=${osd_id_to_remove} | oc -n openshift-storage create -f -
```
  Example Output:
```
job.batch/ocs-osd-removal-0 created
```
  Warning
  This step results in OSD being completely removed from the cluster. Make sure that the correct value of osd_id_to_remove is provided.
Verify that the OSD is removed successfully by checking the status of the ocs-osd-removal pod. A status of Completed confirms that the OSD removal job completed successfully.
```
# oc get pod -l job-name=ocs-osd-removal-${osd_id_to_remove} -n openshift-storage
```
Note
If ocs-osd-removal fails and the pod is not in the expected Completed state, check the pod logs for further debugging. For example:
```
# oc logs ${osd_id_to_remove} -n openshift-storage --tail=-1
```
Delete the persistent volume claim (PVC) resources associated with the OSD to be replaced.
1. Identify the PV associated with the PVC.
```
# oc get -n openshift-storage pvc ocs-deviceset-<x>-<y>-<pvc-suffix>
```
  where, x, y, and pvc-suffix are the values in the DeviceSet identified in an step 4(a).
  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
```
  In this example, the associated PV is local-pv-8137c873.
2. Identify the name of the device to be replaced.
```
# oc get pv local-pv-<pv-suffix> -o yaml | grep path
```
  where, pv-suffix is the value in the PV name identified in an earlier step.
  Example output:
```
path: /mnt/local-storage/localblock/vdc
```
  In this example, the device name is vdc.
3. Identify the prepare-pod associated with the OSD to be replaced.
```
# oc describe -n openshift-storage pvc ocs-deviceset-<x>-<y>-<pvc-suffix> | grep Mounted
```
  where, x, y, and pvc-suffix are the values in the DeviceSet identified in an earlier step.
  Example output:
```
Mounted By:    rook-ceph-osd-prepare-ocs-deviceset-localblock-0-data-0-64knzkc
```
  In this example the prepare-pod name is rook-ceph-osd-prepare-ocs-deviceset-localblock-0-data-0-64knzkc.
4. Delete the osd-prepare pod before removing the associated PVC.
```
# oc delete -n openshift-storage pod rook-ceph-osd-prepare-ocs-deviceset-<x>-<y>-<pvc-suffix>-<pod-suffix>
```
  where, x, y, pvc-suffix, and pod-suffix are the values in the osd-prepare pod name identified in an earlier step.
  Example output:
```
pod "rook-ceph-osd-prepare-ocs-deviceset-localblock-0-data-0-64knzkc" deleted
```
5. Delete the PVC associated with the OSD to be replaced.
```
# oc delete -n openshift-storage pvc ocs-deviceset-<x>-<y>-<pvc-suffix>
```
  where, x, y, and pvc-suffix are the values in the DeviceSet identified in an earlier step.
  Example output:
```
persistentvolumeclaim "ocs-deviceset-localblock-0-data-0-64xjl" deleted
```
Replace the old device and use the new device to create a new OpenShift Container Platform PV.
1. Log in to 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
```
  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
```
2. Record the /dev/disk that is to be replaced using the device name, vdc, identified earlier.
```
# ls -alh /mnt/local-storage/localblock
```
  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
```
3. Find the name of the LocalVolumeSet CR, and remove or comment out the device /dev/disk that is to be replaced.
```
# oc get -n openshift-local-storage localvolumeset
NAME          AGE
localblock   25h
```
Log in to OpenShift Container Platform node with the device to be replaced and remove the old symlink.
```
# oc debug node/worker-0
```
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
```
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
```
  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
```
2. Remove the symlink.
```
# rm /mnt/local-storage/localblock/vdc
```
3. Verify that the symlink is removed.
```
# ls -alh /mnt/local-storage/localblock
```
  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 ..
```
  Important
  For new deployments of OpenShift Container Storage 4.5 or later, LVM is not in use, ceph-volume raw mode is in play instead. Therefore, additional validation is not needed and you can proceed to the next step.
Delete the PV associated with the device to be replaced, which was identified in earlier steps. In this example, the PV name is local-pv-8137c873.
```
# oc delete pv local-pv-8137c873
```
Example output:
```
persistentvolume "local-pv-8137c873" deleted
```
Replace the device with the new device.

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 reseating the same device.

# lsblk

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

In this example, the new device name is vdd.

After the new /dev/disk is available ,it will be auto detected by localvolumeset.

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

# oc get pv | grep 256Gi

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

Create new OSD for new device.
1. Deploy the new OSD by restarting 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
    Example output:
    NAME READY STATUS RESTARTS AGE rook-ceph-operator-85f6494db4-sg62v 1/1 Running 0 1d20h
  2. Delete the rook-ceph-operator.
    # oc delete -n openshift-storage pod rook-ceph-operator-85f6494db4-sg62v
    Example output:
    pod "rook-ceph-operator-85f6494db4-sg62v" deleted
    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
    Example output:
    NAME READY STATUS RESTARTS AGE rook-ceph-operator-85f6494db4-wx9xx 1/1 Running 0 50s
    Creation of the new OSD may take several minutes after the operator restarts.

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

$ oc delete -n openshift-storage job ocs-osd-removal-${osd_id_to_remove}

Verfication steps

Verify that there is a new OSD running and a new PVC created.

# oc get -n openshift-storage pods -l app=rook-ceph-osd

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

# oc get -n openshift-storage pvc | grep localblock

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

Log in to OpenShift Web Console and view the storage dashboard.
Figure 4.7. OSD status in OpenShift Container Platform storage dashboard after device replacement

4.5. 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 SCSI disks.

IBM Z or LinuxONE supports SCSI FCP disk logical units (SCSI disks) as persistent storage devices from external disk storage. A SCSI disk can be identified by using its FCP Device number, two target worldwide port names (WWPN1 and WWPN2), and the logical unit number (LUN). For more information, see Content from www.ibm.com is not included.https://www.ibm.com/support/knowledgecenter/SSB27U_6.4.0/com.ibm.zvm.v640.hcpa5/scsiover.html

Procedure

List all the disks with the following command.

$ lszdev

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

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, it can be replaced with a new disk.

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
```
For example, the following command removes one disk with the device ID 0.0.8204, the WWPN 0x500507630a0b50a4, and the LUN 0x4002403000000000 with the following command:
```
$ chzdev -d 0.0.8204:0x500407630c0b50a4:0x3002b03000000000
```
Append a new SCSI disk with the following command:
```
$ chzdev -e 0.0.8204:0x500507630b1b50a4:0x4001302a00000000
```
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.

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

$ lszdev zfcp-lun
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