How to use the default load-balancer

Canonical Kubernetes includes a default load-balancer. As this is not an essential service for all deployments, it is not enabled by default. This guide explains how to configure and enable the load-balancer.

What you’ll need

This guide assumes the following:

  • You have root or sudo access to the machine.

  • You have a bootstrapped Canonical Kubernetes cluster (see the Getting Started guide).

Check the status and configuration

Find out whether DNS is enabled or disabled with the following command:

sudo k8s status

The load-balancer is not enabled by default, it won’t be listed on the status output unless it has been subsequently enabled.

To check the current configuration of the load-balancer, run the following:

sudo k8s get load-balancer

This should output a list of values like this:

  • cidrs - a list containing CIDR or IP address range definitions of the pool of IP addresses to use

  • l2-mode - whether L2 mode (failover) is turned on

  • l2-interfaces - optional list of interfaces to announce services over (defaults to all)

  • bgp-mode - whether BGP mode is active.

  • bgp-local-asn - the local Autonomous System Number (ASN)

  • bgp-peer-address - the peer address

  • bgp-peer-asn - ASN of the peer network

  • bgp-peer-port - port used on the BGP peer

These values are configured using the k8s setcommand, e.g.:

sudo k8s set load-balancer.l2-mode=true

Note that for the BGP mode, it is necessary to set all the values simultaneously. E.g.

sudo k8s set load-balancer.bgp-mode=true load-balancer.bgp-local-asn=64512 load-balancer.bgp-peer-address=10.0.10.55/32 load-balancer.bgp-peer-asn=64512 load-balancer.bgp-peer-port=7012

Enable the load-balancer

To enable the load-balancer, run:

sudo k8s enable load-balancer

You can now confirm it is working by running:

sudo k8s status

Disable the load-balancer

The default load-balancer can be disabled again with:

sudo k8s disable load-balancer