Chapter 13. Replacing storage nodes

Procedure

1. Log in to OpenShift Web Console and click Compute Nodes.
2. Identify the node that needs to be replaced. Take a note of its Machine Name.

3. Mark the node as unschedulable using the following command:

   $ oc adm cordon <node_name>

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4. Drain the node using the following command:

   $ oc adm drain <node_name> --force --delete-local-data --ignore-daemonsets

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   Important

   This activity may take at least 5-10 minutes or more. Ceph errors generated during this period are temporary and are automatically resolved when the new node is labeled and functional.

5. Click Compute Machines. Search for the required machine.
6. Besides the required machine, click the Action menu (⋮) Delete Machine.
7. Click Delete to confirm the machine deletion. A new machine is automatically created.

8. Wait for new machine to start and transition into Running state.

   Important

   This activity may take at least 5-10 minutes or more.

9. Click Compute Nodes, confirm if the new node is in Ready state.

10. Apply the OpenShift Container Storage label to the new node using any one of the following:

    From User interface

    1. For the new node, click Action Menu (⋮) Edit Labels
    2. Add cluster.ocs.openshift.io/openshift-storage and click Save.

    From Command line interface

    • Execute the following command to apply the OpenShift Container Storage label to the new node:

      $ oc label node <new_node_name> cluster.ocs.openshift.io/openshift-storage=""

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Verification steps

1. Execute the following command and verify that the new node is present in the output:

   $ oc get nodes --show-labels | grep cluster.ocs.openshift.io/openshift-storage= |cut -d' ' -f1

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2. Click Workloads Pods, confirm that at least the following pods on the new node are in Running state:

   • csi-cephfsplugin-*
   • csi-rbdplugin-*
3. Verify that all other required OpenShift Container Storage pods are in Running state.

4. Verify that new OSD pods are running on the replacement node.

   $ oc get pods -o wide -n openshift-storage| egrep -i new-node-name | egrep osd

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5. (Optional) If data encryption is enabled on the cluster, verify that the new OSD devices are encrypted.

   For each of the new 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

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   2. Run “lsblk” and check for the “crypt” keyword beside the ocs-deviceset name(s)

      $ lsblk

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6. If verification steps fail, contact Red Hat Support.

Procedure

1. Log in to OpenShift Web Console and click Compute Nodes.
2. Identify the faulty node and click on its Machine Name.
3. Click Actions Edit Annotations, and click Add More.
4. Add machine.openshift.io/exclude-node-draining and click Save.
5. Click Actions Delete Machine, and click Delete.

6. A new machine is automatically created, wait for new machine to start.

   Important

   This activity may take at least 5-10 minutes or more. Ceph errors generated during this period are temporary and are automatically resolved when the new node is labeled and functional.

7. Click Compute Nodes, confirm if the new node is in Ready state.

8. Apply the OpenShift Container Storage label to the new node using any one of the following:

   From the web user interface

   1. For the new node, click Action Menu (⋮) Edit Labels
   2. Add cluster.ocs.openshift.io/openshift-storage and click Save.

   From the command line interface

   • Execute the following command to apply the OpenShift Container Storage label to the new node:

     $ oc label node <new_node_name> cluster.ocs.openshift.io/openshift-storage=""

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9. [Optional]: If the failed Google Cloud instance is not removed automatically, terminate the instance from Google Cloud console.

Verification steps

1. Execute the following command and verify that the new node is present in the output:

   $ oc get nodes --show-labels | grep cluster.ocs.openshift.io/openshift-storage= |cut -d' ' -f1

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2. Click Workloads Pods, confirm that at least the following pods on the new node are in Running state:

   • csi-cephfsplugin-*
   • csi-rbdplugin-*
3. Verify that all other required OpenShift Container Storage pods are in Running state.

4. Verify that new OSD pods are running on the replacement node.

   $ oc get pods -o wide -n openshift-storage| egrep -i new-node-name | egrep osd

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5. (Optional) If data encryption is enabled on the cluster, verify that the new OSD devices are encrypted.

   For each of the new 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

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   2. Run “lsblk” and check for the “crypt” keyword beside the ocs-deviceset name(s)

      $ lsblk

      Copy to Clipboard Toggle word wrap
6. If verification steps fail, contact Red Hat Support.