Assign Extended Resources to a Container

    This page shows how to assign extended resources to a Container.

    You need to have a Kubernetes cluster, and the kubectl command-line tool must be configured to communicate with your cluster. It is recommended to run this tutorial on a cluster with at least two nodes that are not acting as control plane hosts. If you do not already have a cluster, you can create one by using or you can use one of these Kubernetes playgrounds:

    To check the version, enter kubectl version.

    Before you do this exercise, do the exercise in Advertise Extended Resources for a Node. That will configure one of your Nodes to advertise a dongle resource.

    To request an extended resource, include the resources:requests field in your Container manifest. Extended resources are fully qualified with any domain outside of *.kubernetes.io/. Valid extended resource names have the form example.com/foo where example.com is replaced with your organization’s domain and foo is a descriptive resource name.

    Here is the configuration file for a Pod that has one Container:

    In the configuration file, you can see that the Container requests 3 dongles.

    Create a Pod:

    1. kubectl apply -f https://k8s.io/examples/pods/resource/extended-resource-pod.yaml

    Verify that the Pod is running:

    1. kubectl get pod extended-resource-demo

    Describe the Pod:

      The output shows dongle requests:

      Here is the configuration file for a Pod that has one Container. The Container requests two dongles.

      2. kind: Pod
      3. metadata:
      4.   name: extended-resource-demo-2
      5. spec:
      6.   containers:
      7.   - name: extended-resource-demo-2-ctr
      8.     image: nginx
      9.     resources:
      10.       requests:
      12.         example.com/dongle: 2

      Kubernetes will not be able to satisfy the request for two dongles, because the first Pod used three of the four available dongles.

      Attempt to create a Pod:

      1. kubectl apply -f https://k8s.io/examples/pods/resource/extended-resource-pod-2.yaml

      Describe the Pod

      1. kubectl describe pod extended-resource-demo-2

      The output shows that the Pod cannot be scheduled, because there is no Node that has 2 dongles available:

      View the Pod status:

      1. kubectl get pod extended-resource-demo-2

      The output shows that the Pod was created, but not scheduled to run on a Node. It has a status of Pending:

      1. NAME                       READY     STATUS    RESTARTS   AGE
      2. extended-resource-demo-2   0/1       Pending   0          6m
      1. kubectl delete pod extended-resource-demo
      2. kubectl delete pod extended-resource-demo-2

      For cluster administrators