By watching changes to a list of Endpoints:

GET /api/v1/watch/namespaces/{namespace}/endpoints

Headless Services are a group of Pod IPs. Pod IPs are not (generally) available outside the cluster/cloud-provider.

Are you trying to get external IPs for a headless service or are you within the same network (e.g. in the GCE project) but not in the cluster?

The DNS addon is exactly what you're after. From the docs:

For example, if you have a Service called "my-service" in Kubernetes Namespace "my-ns" a DNS record for "my-service.my-ns" is created. Pods which exist in the "my-ns" Namespace should be able to find it by simply doing a name lookup for "my-service". Pods which exist in other Namespaces must qualify the name as "my-service.my-ns". The result of these name lookups is the cluster IP.

And in the case of a headless service:

DNS is configured to return multiple A records (addresses) for the Service name, which point directly to the Pods backing the Service.

However, this service is only available inside the cluster. But KubeDNS is just another pod:

kubectl get po --namespace=kube-system
kubectl describe po kube-dns-pod-name --namespace=kube-system

Which means you can create a service with an externally accessible address to expose this service. Just use a selector matching your kube-dns pod label.

http://kubernetes.io/v1.1/docs/user-guide/services.html#dns https://github.com/kubernetes/kubernetes/blob/release-1.1/cluster/addons/dns/README.md