kubernetes
/
website
mirror of https://github.com/kubernetes/website.git
1
0
Fork 0
Code Issues Projects Releases Wiki Activity
website/content/en/docs/tasks/configure-pod-container/extended-resource.md

3.3 KiB
Raw Blame History

title content_template weight
Assign Extended Resources to a Container templates/task 40

{{% capture overview %}}

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

{{< feature-state state="stable" >}}

{{% /capture %}}

{{% capture prerequisites %}}

{{< include "task-tutorial-prereqs.md" >}} {{< version-check >}}

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.

{{% /capture %}}

{{% capture steps %}}

Assign an extended resource to a Pod

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:

{{< code file="extended-resource-pod.yaml" >}}

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

Create a Pod:

kubectl create -f https://k8s.io/docs/tasks/configure-pod-container/extended-resource-pod.yaml

Verify that the Pod is running:

kubectl get pod extended-resource-demo

Describe the Pod:

kubectl describe pod extended-resource-demo

The output shows dongle requests:

Limits:
  example.com/dongle: 3
Requests:
  example.com/dongle: 3

Attempt to create a second Pod

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

{{< code file="extended-resource-pod-2.yaml" >}}

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:

kubectl create -f https://k8s.io/docs/tasks/configure-pod-container/extended-resource-pod-2.yaml

Describe the Pod

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:

Conditions:
  Type    Status
  PodScheduled  False
...
Events:
  ...
  ... Warning   FailedScheduling  pod (extended-resource-demo-2) failed to fit in any node
fit failure summary on nodes : Insufficient example.com/dongle (1)

View the Pod status:

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:

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

Clean up

Delete the Pod that you created for this exercise:

kubectl delete pod extended-resource-demo-2

{{% /capture %}}

{{% capture whatsnext %}}

For application developers

For cluster administrators

{{% /capture %}}