openstack-operator/doc/source/deployment-guide/setup-load-balancer.rst

Setup Load Balancer

The load balancer which will be distributing requests across all of the Kubernetes API servers will be HAproxy.

Note

We do not suggest using HAproxy to distribute load across all of the ingress controllers. The primary reason being that it introduces an extra hop in the network for no large benefit. The ingress should be bound directly on the virtual IP.

The following example assumes that you have 3 controllers, with their IP addresses being 10.0.0.1, 10.0.0.2, 10.0.0.3. It also assumes that all of the Kubernetes API servers will be listening on port 16443 and it will be listening on port 6443.

You'll have to create a configuration file on the local system first:

$ mkdir /etc/haproxy
$ cat <<EOF | tee /etc/haproxy/haproxy.cfg
listen kubernetes
  mode tcp
  bind 0.0.0.0:6443
  timeout connect 30s
  timeout client 4h
  timeout server 4h
  server ctl1 10.0.0.1:16443 check
  server ctl2 10.0.0.2:16443 check
  server ctl3 10.0.0.3:16443 check
EOF

Once you've setup the configuration file, you can start up the containerized instance of HAproxy:

$ docker run --net=host \
             --volume=/etc/haproxy:/usr/local/etc/haproxy:ro \
             --detach \
             --restart always \
             --name=haproxy \
             haproxy:2.2

You'll also need to make sure that you have a DNS record pointing towards your virtual IP address. It is also recommended that you create a wildcard DNS as well to allow multiple hosts for the ingress without needing extra changes in your DNS, something like this:

cloud.vexxhost.net.  86400   IN  A   10.0.0.200
*.cloud.vexxhost.net 86400   IN      A       10.0.0.200