kubernetes/docs/user-guide/configmap/README.md
2016-02-23 13:27:54 -05:00

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<h2>PLEASE NOTE: This document applies to the HEAD of the source tree</h2>
If you are using a released version of Kubernetes, you should
refer to the docs that go with that version.
Documentation for other releases can be found at
[releases.k8s.io](http://releases.k8s.io).
</strong>
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# ConfigMap example
## Step Zero: Prerequisites
This example assumes you have a Kubernetes cluster installed and running, and that you have
installed the `kubectl` command line tool somewhere in your path. Please see the [getting
started](../../../docs/getting-started-guides/) for installation instructions for your platform.
## Step One: Create the ConfigMap
A ConfigMap contains a set of named strings.
Use the [`examples/configmap/configmap.yaml`](configmap.yaml) file to create a ConfigMap:
```console
$ kubectl create -f docs/user-guide/configmap/configmap.yaml
```
You can use `kubectl` to see information about the ConfigMap:
```console
$ kubectl get configmap
NAME DATA
test-secret 2
$ kubectl describe configMap test-configmap
Name: test-configmap
Labels: <none>
Annotations: <none>
Data
====
data-1: 7 bytes
data-2: 7 bytes
```
View the values of the keys with `kubectl get`:
```console
$ cluster/kubectl.sh get configmaps test-configmap -o yaml
apiVersion: v1
data:
data-1: value-1
data-2: value-2
kind: ConfigMap
metadata:
creationTimestamp: 2016-02-18T20:28:50Z
name: test-configmap
namespace: default
resourceVersion: "1090"
selfLink: /api/v1/namespaces/default/configmaps/test-configmap
uid: 384bd365-d67e-11e5-8cd0-68f728db1985
```
## Step Two: Create a pod that consumes a configMap in environment variables
Use the [`examples/configmap/env-pod.yaml`](env-pod.yaml) file to create a Pod that consumes the
ConfigMap in environment variables.
```console
$ kubectl create -f docs/user-guide/configmap/env-pod.yaml
```
This pod runs the `env` command to display the environment of the container:
```console
$ kubectl logs secret-test-pod
KUBE_CONFIG_1=value-1
KUBE_CONFIG_2=value-2
```
## Step Three: Create a pod that sets the command line using ConfigMap
Use the [`examples/configmap/command-pod.yaml`](env-pod.yaml) file to create a Pod with a container
whose command is injected with the keys of a ConfigMap
```console
$ kubectl create -f docs/user-guide/configmap/env-pod.yaml
```
This pod runs an `echo` command to display the keys:
```console
value-1 value-2
```
## Step Four: Create a pod that consumes a configMap in a volume
Pods can also consume ConfigMaps in volumes. Use the [`examples/configmap/volume-pod.yaml`](volume-pod.yaml) file to create a Pod that consume the ConfigMap in a volume.
```console
$ kubectl create -f docs/user-guide/configmap/volume-pod.yaml
```
This pod runs a `cat` command to print the value of one of the keys in the volume:
```console
value-1
```
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