Description of problem:

When changes are made to SDN plugin, the master controller will fail to start when there are headless services in the cluster. 

Error Message: 

[run_components.go:384] SDN initialization failed: Error: Existing service with IP: None is not part of service network: 172.30.0.0/16

https://kubernetes.io/docs/concepts/services-networking/service/#headless-services


Code that checks and errors out. 

https://github.com/openshift/openshift-sdn/blob/master/plugins/osdn/master.go#L111-L120

Version-Release number of selected component (if applicable):


How reproducible:
100%

Steps to Reproduce:
1. Create headless service 

# oc create -f - << EOF
apiVersion: v1
kind: Service
metadata:
  name: hello-openshift
spec:
  selector:
    name: hello-openshift
  portalIP: None
  clusterIP: None
  ports:
  - port: 8080
    protocol: TCP
    targetPort: 8080
EOF
```

2. Change sdn plugin 

Master
  # sed -i 's/openshift-ovs-subnet/openshift-ovs-multitenant/g' /etc/origin/master/master-config.yaml
  # sed -i 's/openshift-ovs-subnet/openshift-ovs-multitenant/g' /etc/origin/node/node-config.yaml
 
Node
  # sed -i 's/openshift-ovs-subnet/openshift-ovs-multitenant/g' /etc/origin/node/node-config.yaml


3. Restart masters and nodes 


Actual results:

SDN initialization failed: Error: Existing service with IP: None is not part of service network: 172.30.0.0/16


Expected results:
The SDN not to fail with hitting headless services 


Additional info:

The metrics and logging deployer configures headless services that have 

  clusterIP: None

Example: 

https://github.com/openshift/origin-metrics/blob/master/deployer/templates/hawkular-cassandra.yaml#L47