Chapter 5. Replacing storage nodes

Procedure

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

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

   $ oc adm cordon <node_name>

5. Drain the node using the following command:

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

   Important

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

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

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

   Important

   This activity may take at least 5-10 minutes.

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

11. 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=""

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

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

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

   1. Create a debug pod and open a chroot environment for the host.

      $ oc debug node new-node-name
      $ chroot /host

   2. Verify the devices are encrypted.

      $ dmsetup ls | grep ocs-deviceset
      ocs-deviceset-0-data-0-57snx-block-dmcrypt (253:1)

      $ lsblk | grep ocs-deviceset
      `-ocs-deviceset-0-data-0-57snx-block-dmcrypt 253:1    0   512G  0 crypt

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. 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=""

9. 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

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

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

12. 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

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

    1. Create a debug pod and open a chroot environment for the host.

       $ oc debug node new-node-name
       $ chroot /host

    2. Verify the devices are encrypted.

       $ dmsetup ls | grep ocs-deviceset
       ocs-deviceset-0-data-0-57snx-block-dmcrypt (253:1)

       $ lsblk | grep ocs-deviceset
       `-ocs-deviceset-0-data-0-57snx-block-dmcrypt 253:1    0   512G  0 crypt

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