private Set<String> reachableIpAddresses(Node node, CloudAccount cloudAccount) {
        Set<String> reachable = new LinkedHashSet<>(node.ipConfig().primary());
        boolean forceIpv6 = ipv6AwsTargetGroups.with(Dimension.CLOUD_ACCOUNT, cloudAccount.account()).value();
        var protocol = forceIpv6 ? LoadBalancerService.Protocol.ipv6 :
                service.protocol(node.cloudAccount().isExclave(nodeRepository.zone()));
        // Remove addresses unreachable by the load balancer service
        switch (protocol) {
            case ipv4 -> reachable.removeIf(IP::isV6);
            case ipv6 -> reachable.removeIf(IP::isV4);
        }
        return reachable;
    }
Find IP addresses reachable by the load balancer service
node-repository/src/main/java/com/yahoo/vespa/hosted/provision/provisioning/LoadBalancerProvisioner.java