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Canonical Kubernetes

Versions Supported​

Native Load Balancer​

The Canonical Kubernetes pack includes a built-in load balancer that you can enable directly from the pack configuration. When enabled, Kubernetes Services of type LoadBalancer receive an external IP address from a Classless Inter-Domain Routing (CIDR) block or IP range that you specify in the pack values. This removes the need to install a separate load balancer pack, such as MetalLB, to publish services on clusters that use Canonical Kubernetes.

The built-in load balancer runs in Layer 2 (L2) mode. In L2 mode, the load balancer announces the assigned IP address on the local network by responding to Address Resolution Protocol (ARP) requests, which makes the service reachable from other devices on the same subnet. Choose an address range that belongs to the same Layer 2 network as your cluster hosts and that does not overlap with any other allocated IP addresses.

Native load balancer support was introduced in Canonical Kubernetes pack version 1.35.2.

Prerequisites​

  • A cluster profile that uses the Canonical Kubernetes pack version 1.35.2 or later.

  • A CIDR block or an IP range on the same Layer 2 network as your cluster hosts. Reserve the addresses for the load balancer, and confirm that no other devices in the network use them.

Enablement​

  1. Log in to Palette.

  2. From the left main menu, select Profiles.

  3. Select the cluster profile that you plan to use, and then select the Canonical Kubernetes layer.

  4. In the YAML editor, locate the cluster-config section inside the config block. Add a load-balancer entry with the following parameters. Replace <load-balancer-range> with the CIDR block or IP range that the load balancer must use when it assigns external IP addresses.

    config: |
      cluster-config:
        network:
          enabled: false
        ingress:
          enabled: false
        metrics-server:
          enabled: false
        local-storage:
          enabled: false
        load-balancer:
          enabled: true
          cidrs:
            - <load-balancer-range>
          l2-mode: true

    The following table describes each load-balancer parameter.

    ParameterDescription
    enabledEnables the built-in load balancer in the Canonical Kubernetes distribution. Set to true.
    cidrsA list of address ranges that the load balancer draws from when it assigns an external IP address to a Service of type LoadBalancer. Each list item can be a CIDR block, such as 10.10.177.0/24, or an IP range, such as 10.10.177.204-10.10.177.208.
    l2-modeEnables Layer 2 announcement of the assigned IP addresses through ARP. Set to true for environments where Border Gateway Protocol (BGP) is not available.

  5. Save the changes to the cluster profile.

  6. Deploy a cluster with this cluster profile, or update an existing cluster to the new profile version.