High Availability (HA) for the Service Kubernetes Cluster

Prerequisites

  • Ensure that the local_repo.yml playbook has been run successfully at least once. Before running it, verify that the /opt/omnia/input/project_default/software_config.json file contains {"name": "service_k8s"} in the softwares list.

  • To enable and configure the HA for Service cluster, fill up the necessary parameters in the high_availability_config.yml config file present in the /opt/omnia/input/project_default/ directory. Once the config file is updated, run the prepare_oim.yml playbook.

    Parameters for Service Cluster HA

    Parameter

    Details

    cluster_name

    • Type: String

    • Captures the name of the service cluster on which HA will be set up. Default value: service_cluster

    enable_k8s_ha

    • Type: Boolean

    • Possible values: true

    • Default value: true

    • Indicates whether to enable HA for the Kubernetes (K8s) service node or not. Set to true to enable.

    virtual_ip_address

    • Type: String

    • This is a mandatory and user-configurable parameter.

    • Captures the virtual IP address for the K8s service node HA setup. Ensure that the virtual_ip_address does not belong to the dynamic_range or static_range mentioned in the network_spec.yml.

    • Default value: 172.16.107.1

    external_loadbalancer_ip

    • Type: IP address

    • Specify this to use an external load balancer instead of the kube-vip loadbalancer.

    loadbalancer_port

    • Type: Port number

    • Captures the port for the external loadbalancer.

    • This port must be unique and not in use.

    Note

    Ensure to not use the 6443 port.

    active_node_service_tag

    • Type: Comma-separated list

    • List of service tags of active K8s service nodes. Multiple tags can be provided with commas.

Note

  • Once the prepare_oim.yml playbook has been executed, any subsequent edits to the high_availability_config.yml or functional_groups_config.yml files will not take effect. To apply changes made to these configuration files, you must re-run the prepare_oim.yml playbook.

  • The virtual IP addresses specified in the high_availability_config.yml file must be within the same subnet as the admin network.

Sample

service_k8s_cluster_ha:
    - cluster_name: service_cluster
      enable_k8s_ha: true
      virtual_ip_address: ""
      external_loadbalancer_ip: ""
      loadbalancer_port:
      active_node_service_tags: [ABCD123, DEF4567]

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