PreferDualStack Admission Controller
Currently Kubernetes services are created in single stack mode by default, defaulting to primary address family of the cluster.
This is a mutating webhook admission controller that adds ipFamilyPolicy: PreferDualStack to all newly created services if the field is not explicitely specified, making dual-stack the default.
Installation
kubectl apply -f https://raw.githubusercontent.com/tibordp/prefer-dual-stack-webhook/master/deploy.yaml
Demo
| Before |
Afrer |
|
```bash
> kubectl apply -f - < kubectl describe svc dummy
Name: dummy
Namespace: default
Labels:
Annotations:
Selector: app=dummy
Type: ClusterIP
IP Family Policy: SingleStack
IP Families: IPv4
IP: 10.96.200.4
IPs: 10.96.200.4
Port: 80/TCP
TargetPort: 80/TCP
Endpoints:
Session Affinity: None
Events:
```
|
```bash
> kubectl apply -f - < kubectl describe svc dummy
Name: dummy
Namespace: default
Labels:
Annotations:
Selector: app=dummy
Type: ClusterIP
IP Family Policy: PreferDualStack
IP Families: IPv4,IPv6
IP: 10.96.19.47
IPs: 10.96.19.47,fd00:10:96::f31
Port: 80/TCP
TargetPort: 80/TCP
Endpoints:
Session Affinity: None
Events:
```
|
Acknowledgements
Admission controller webhook boilerplate adapted from douglasmakey/admissioncontroller by Douglas Makey Mendez Molero.