Updating Kubernetes Resource

Using kubectl edit

You can also use kubectl edit rs @rs_name and edit the yaml template

kubectl edit rs v1-web

Using kubectl patch

  • We can use kubectl patch to update the template of running resource.
  • You can pass either JSON or YAML when patching the resource.
  • kubectl patch @resource_type @resource_name --patch @template_subset
k patch pods v1-web --patch '{"metadata": {"labels": {"version": "v2"}}}'
  • In above command --patch takes a Kubernetes configuration file.
  • We can pass yaml like structure to --patch but I don't think will look good on a command. Plus the spacing and tabs will be tricky.
  • We are using JSON to send the patch.
  • We define properties we want to override. Notice that it is a subset of a full Kubernetes config.
  • When patching like this, we need to structure our data from root just like we do in config file.

Using kubectl apply

  • To update Resource Template for running resource as well.
  • To update the template for running resource you use kubectl apply.
  • Change you label env to prod at the moment.
➜ kubectl apply -f pods.yaml           
pod/v1-web configured
  • List the labels again and you will see labels are changed.
➜ kubectl get pods -L version,env
NAME     READY   STATUS    RESTARTS   AGE     VERSION   ENV
v1-web   1/1     Running   0          8m51s   v1        prod