karmada/samples/guestbook

Propagate CRD application

The following steps demonstrating how to propagate a Guestbook which is defined by CRD.

Assume you are under the guestbook directory.

cd samples/guestbook

and set the KUBECONFIG environment with Karmada configuration.

export KUBECONFIG=${HOME}/.kube/karmada.config

1. Create Guestbook CRD in Karmada

kubectl apply -f guestbooks-crd.yaml 

The CRD should be applied to karmada-apiserver.

2. Create ClusterPropagationPolicy that will propagate Guestbook CRD to member cluster

kubectl apply -f guestbooks-clusterpropagationpolicy.yaml

The CRD will be propagated to member clusters according to the rules defined in ClusterPropagationPolicy

Note: We can only use ClusterPropagationPolicy not PropagationPolicy here. Please refer to FAQ Difference between PropagationPolicy and ClusterPropagationPolicy for more details.

3. Create a Guestbook named guestbook-sample in Karmada

kubectl apply -f guestbook.yaml

4. Create PropagationPolicy that will propagate guestbook-sample to member cluster

kubectl apply -f guestbooks-propagationpolicy.yaml

5. Check the guestbook-sample status from Karmada

kubectl get guestbook -oyaml

6. Create OverridePolicy that will override the size field of guestbook-sample in member cluster

kubectl apply -f guestbooks-overridepolicy.yaml

7. Check the size field of guestbook-sample from member cluster

kubectl --kubeconfig=${HOME}/.kube/members.config config use-context member1
kubectl --kubeconfig=${HOME}/.kube/members.config get guestbooks -o yaml

If it works as expected, the .spec.size will be overwritten to 4.