John Mulhausen
61 lines
1.8 KiB
Markdown
61 lines
1.8 KiB
Markdown
---
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layout: docwithnav
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title: "Downward API example"
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---
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# Downward API example
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Following this example, you will create a pod with a container that consumes the pod's name and
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namespace using the [downward API](../downward-api.html).
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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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{% highlight console %}
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{% raw %}
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$ kubectl create -f docs/user-guide/downward-api/dapi-pod.yaml
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{% endraw %}
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{% endhighlight %}
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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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{% highlight console %}
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{% raw %}
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$ kubectl logs dapi-test-pod | grep POD_
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2015-04-30T20:22:18.568024817Z MY_POD_NAME=dapi-test-pod
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2015-04-30T20:22:18.568087688Z MY_POD_NAMESPACE=default
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2015-04-30T20:22:18.568092435Z MY_POD_IP=10.0.1.6
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{% endraw %}
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{% endhighlight %}
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