@Override
    public boolean supports(NodeType nodeType, ClusterSpec.Type clusterType) {
        // Shared routing layer only supports routing to tenant nodes
        return nodeType == NodeType.tenant && clusterType.isContainer();
    }
This implementation of {@link LoadBalancerService} returns the load balancer(s) that exist by default in the shared
routing layer.
<p>
Since such load balancers always exist, we can return the hostname of the routing layer VIP directly. Nothing has to
be provisioned.

@author ogronnesby
node-repository/src/main/java/com/yahoo/vespa/hosted/provision/lb/SharedLoadBalancerService.java