Dual Stack Support

[majst01]

Upstream References:

• Support IPv6 gardener/gardener#8899

The main difference is that now the insfrastructure extension can put the Cidrs of workers/pods/services into the Status of the Infrastructure Resource. In The Shoot Spec only the IPFamilies which should be used must be specified:

kind: Shoot
apiVersion: core.gardener.cloud/v1beta1
metadata:
  ...
spec:
  ...
  networking:
    type: ...
    pods: 192.168.128.0/17 # optional
    nodes: 192.168.0.0/18 # optional
    services: 192.168.64.0/18 # optional
    ipFamilies:
      - IPv4
      - IPv6

See THE AWS Extension for reference: https://github.com/gardener/gardener-extension-provider-aws/blob/master/docs/usage/ipv6.md and

kube-controller-manager

must be configured that he adds both AFs to the node like:

--node-cidr-mask-size-v4=23
--node-cidr-mask-size-v6=80 # see https://github.com/gardener/gardener/blob/master/pkg/component/kubernetes/controllermanager/controllermanager.go#L676
--allocate-node-cidrs=true
--cluster-cidr=10.244.128.0/18, 2001:db8::/64