Add a controller node

This section describes how to add a new control plane node to the existing MOSK deployment.

To add an OpenStack controller node:

  1. Add a bare-metal host to the MOSK cluster as described in Add a bare-metal host.

    When adding the bare-metal host YAML file, specify the following OpenStack control plane node labels for the OpenStack control plane services such as database, messaging, API, schedulers, conductors, L3 and L2 agents:

    • openstack-control-plane=enabled

    • openstack-gateway=enabled

    • openvswitch=enabled

  2. Create a Kubernetes machine in your cluster as described in Add a machine.

    When adding the machine, verify that OpenStack control plane node has the following labels:

    • openstack-control-plane=enabled

    • openstack-gateway=enabled

    • openvswitch=enabled

    Note

    Depending on the applications that were colocated on the failed controller node, you may need to specify some additional labels, for example, ceph_role_mgr=true and ceph_role_mon=true . To successfuly replace a failed mon and mgr node, refer to Ceph cluster lifecycle management.

  3. Verify that the node is in the Ready state through the Kubernetes API:

    kubectl get node <NODE-NAME> -o wide | grep Ready

  4. Verify that the node has all required labels described in the previous steps:

    kubectl get nodes --show-labels

  5. Configure new Octavia health manager resources:

    1. Rerun the octavia-create-resources job:

      kubectl -n osh-system exec -t <OS-CONTROLLER-POD> -c osdpl osctl-job-rerun octavia-create-resources openstack

    2. Wait until the Octavia health manager pod on the newly added control plane node appears in the Running state:

      kubectl -n openstack get pods -o wide | grep <NODE_ID> | grep octavia-health-manager

      Note

      If the pod is in the crashloopbackoff state, remove it:

      kubectl -n openstack delete pod <OCTAVIA-HEALTH-MANAGER-POD-NAME>

    3. Verify that an OpenStack port for the node has been created and the node is in the Active state:

      kubectl -n openstack exec -t <KEYSTONE-CLIENT-POD-NAME> openstack port show octavia-health-manager-listen-port-<NODE-NAME>

  6. Strongly recommended. Back up MKE as described in Create backups of Mirantis Kubernetes Engine.

    Since the procedure above modifies the cluster configuration, a fresh backup is required to restore the cluster in case further reconfigurations fail.