Kustomize Output

In the previous lesson, we examined the Kustomize build command and its role in transforming resource definitions into final configurations, which are then output to the console. It is important to note that these generated configurations are not automatically deployed to your Kubernetes cluster—running commands like kubectl get pods, kubectl get deployments, or kubectl get services right after the build will not show any new resources.

Deploying Configurations Using Pipes

To deploy the generated configurations, you can use the Linux pipe utility. This allows you to feed the output of the Kustomize build directly into the Kubernetes API using the kubectl apply command. Here’s an example:

$ kustomize build k8s/ | kubectl apply -f -
service/nginx-loadbalancer-service created
deployment.apps/nginx-deployment created

In this command, the pipe (|) directs the output from kustomize build k8s/ into kubectl apply -f -, thus creating the nginx deployment and its corresponding service.

Deploying Configurations Natively with kubectl

Alternatively, you can accomplish the same deployment natively with kubectl using the -k flag. This flag tells kubectl to locate and process the kustomization.yaml file in the specified directory:

$ kubectl apply -k k8s/
service/nginx-loadbalancer-service created
deployment.apps/nginx-deployment created

Both methods will effectively deploy your generated configurations to your Kubernetes cluster.

Deleting Configurations

Removing resources deployed via Kustomize is almost identical to applying them. You simply replace the word apply with delete.

Using the Pipe Method

Delete the resources using the pipe method by running:

$ kustomize build k8s/ | kubectl delete -f -
service "nginx-loadbalancer-service" deleted
deployment.apps "nginx-deployment" deleted

Using kubectl with the -k Flag

Or, delete the resources natively with kubectl:

$ kubectl delete -k k8s/
service "nginx-loadbalancer-service" deleted
deployment.apps "nginx-deployment" deleted