Check your version of kubectl

kubectl version

*If you have 1.21 or above of kubectl you will have access to kubectl kustomize which is the recommended method. If you aren't on version 1.21 or above, upgrade kubectl.

*You could also download/use the 'kutomize' binary seperatly but the cmds are different.

Viewing Kustomize Configs - (Using kubectl kustomize integration)

kubectl kustomize .
kubectl kustomize overlays/dev/
kubectl kustomize overlays/prod/

Applying Kustomize Configs - (Using kubectl kustomize integration)

kubectl apply -k .
kubectl apply -k overlays/dev/
kubectl apply -k overlays/prod/

Note: if you get field is immutable error, check your configuration and try deleting the resources then applying again.

Creating Namespaces if you dont have them already

kubectl create namespace dev; kubectl create namespace prod;

Accessing the application

minikube service kustom-mywebapp-v1
minikube service kustom-mywebapp-v1 -n dev
minikube service kustom-mywebapp-v1 -n prod

References:

https://github.com/kubernetes-sigs/kustomize/blob/master/README.md https://kubectl.docs.kubernetes.io/guides/config_management/offtheshelf/