Chapter 14. Replacing storage nodes

Procedure

1. Log in to the OpenShift Web Console, and click Compute Nodes.
2. Identify the node that you need to replace. Take a note of its Machine Name.

3. Mark the node as unschedulable:

   $ oc adm cordon <node_name>

   <node_name>

   Specify the name of node that you need to replace.

4. Drain the node:

   $ oc adm drain <node_name> --force --delete-emptydir-data=true --ignore-daemonsets

   Important

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

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

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

   Important

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

9. Click Compute Nodes. Confirm that the new node is in Ready state.

10. Apply the OpenShift Data Foundation label to the new node:

    From the 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

    • Apply the OpenShift Data Foundation label to the new node:

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

    <new_node_name>

    Specify the name of the new node.

Verification steps

1. 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 the other required OpenShift Data Foundation pods are in Running state.

4. Verify that the new Object Storage Device (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 cluster-wide encryption is enabled on the cluster, verify that the new OSD devices are encrypted.

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

   1. Create a debug pod and open a chroot environment for the one or more selected hosts:

      $ oc debug node/<node_name>

      $ chroot /host

   2. Display the list of available block devices:

      $ lsblk

      Check for the crypt keyword beside the one or more ocs-deviceset names.

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

Procedure

1. Log in to the 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 might take at least 5 - 10 minutes or more. Ceph errors generated during this period are temporary and are automatically resolved when you label the new node, and it is functional.

7. Click Compute Nodes. Confirm that the new node is in Ready state.

8. Apply the OpenShift Data Foundation label to the new node using any one of the following:

   From the 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

   • Apply the OpenShift Data Foundation label to the new node:

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

   <new_node_name>

   Specify the name of the new node.

9. Optional: If the failed Red Hat OpenStack Platform instance is not removed automatically, terminate the instance from Red Hat OpenStack Platform console.

Verification steps

1. 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 the other required OpenShift Data Foundation pods are in Running state.

4. Verify that the new Object Storage Device (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 cluster-wide encryption is enabled on the cluster, verify that the new OSD devices are encrypted.

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

   1. Create a debug pod and open a chroot environment for the one or more selected hosts:

      $ oc debug node/<node_name>

      $ chroot /host

   2. Display the list of available block devices:

      $ lsblk

      Check for the crypt keyword beside the one or more ocs-deviceset names.

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