mirror of https://github.com/k3s-io/k3s
72 lines
2.5 KiB
Markdown
72 lines
2.5 KiB
Markdown
<!-- BEGIN MUNGE: UNVERSIONED_WARNING -->
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<!-- BEGIN STRIP_FOR_RELEASE -->
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<img src="http://kubernetes.io/img/warning.png" alt="WARNING"
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width="25" height="25">
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<img src="http://kubernetes.io/img/warning.png" alt="WARNING"
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width="25" height="25">
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<img src="http://kubernetes.io/img/warning.png" alt="WARNING"
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width="25" height="25">
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<img src="http://kubernetes.io/img/warning.png" alt="WARNING"
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width="25" height="25">
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<img src="http://kubernetes.io/img/warning.png" alt="WARNING"
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width="25" height="25">
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<h2>PLEASE NOTE: This document applies to the HEAD of the source tree</h2>
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If you are using a released version of Kubernetes, you should
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refer to the docs that go with that version.
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<strong>
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The latest 1.0.x release of this document can be found
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[here](http://releases.k8s.io/release-1.0/docs/user-guide/downward-api/README.md).
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Documentation for other releases can be found at
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[releases.k8s.io](http://releases.k8s.io).
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</strong>
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--
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<!-- END STRIP_FOR_RELEASE -->
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<!-- END MUNGE: UNVERSIONED_WARNING -->
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# Downward API example
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Following this example, you will create a pod with a containers that consumes the pod's name and
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namespace using the [downward API](../downward-api.md).
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## Step Zero: Prerequisites
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This example assumes you have a Kubernetes cluster installed and running, and that you have
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installed the `kubectl` command line tool somewhere in your path. Please see the [getting
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started](../../../docs/getting-started-guides/) for installation instructions for your platform.
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## Step One: Create the pod
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Containers consume the downward API using environment variables. The downward API allows
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containers to be injected with the name and namespace of the pod the container is in.
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Use the [`examples/downward-api/dapi-pod.yaml`](dapi-pod.yaml) file to create a Pod with a container that consumes the
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downward API.
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```console
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$ kubectl create -f docs/user-guide/downward-api/dapi-pod.yaml
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```
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### Examine the logs
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This pod runs the `env` command in a container that consumes the downward API. You can grep
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through the pod logs to see that the pod was injected with the correct values:
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```console
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$ kubectl logs dapi-test-pod | grep POD_
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2015-04-30T20:22:18.568024817Z POD_NAME=dapi-test-pod
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2015-04-30T20:22:18.568087688Z POD_NAMESPACE=default
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```
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<!-- BEGIN MUNGE: GENERATED_ANALYTICS -->
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[]()
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<!-- END MUNGE: GENERATED_ANALYTICS -->
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