website/docs/tutorials/configuration/configure-redis-using-confi...

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---
approvers:
- eparis
- pmorie
title: Configuring Redis using a ConfigMap
---
{% capture overview %}
This page provides a real world example of how to configure Redis using a ConfigMap and builds upon the [Using ConfigMap Data in Pods](/docs/tasks/configure-pod-container/configure-pod-configmap/) and [Configure Containers Using a ConfigMap](/docs/tasks/configure-pod-container/configmap/) tasks.
{% endcapture %}
{% capture objectives %}
* Create a ConfigMap.
* Create a pod specification using the ConfigMap.
* Create the pod.
* Verify that the configuration was correctly applied.
{% endcapture %}
{% capture prerequisites %}
* {% include task-tutorial-prereqs.md %}
* Understand [Using ConfigMap Data in Pods](/docs/tasks/configure-pod-container/configure-pod-configmap/).
* Understand [Configure Containers Using a ConfigMap](/docs/tasks/configure-pod-container/configmap/).
{% endcapture %}
{% capture lessoncontent %}
## Real World Example: Configuring Redis using a ConfigMap
You can follow the steps below to configure a Redis cache using data stored in a ConfigMap.
1. Create a ConfigMap from the `docs/user-guide/configmap/redis/redis-config` file:
```shell
kubectl create configmap example-redis-config --from-file=docs/user-guide/configmap/redis/redis-config
kubectl get configmap example-redis-config -o yaml
```
```yaml
apiVersion: v1
data:
redis-config: |
maxmemory 2mb
maxmemory-policy allkeys-lru
kind: ConfigMap
metadata:
creationTimestamp: 2016-03-30T18:14:41Z
name: example-redis-config
namespace: default
resourceVersion: "24686"
selfLink: /api/v1/namespaces/default/configmaps/example-redis-config
uid: 460a2b6e-f6a3-11e5-8ae5-42010af00002
```
1. Create a pod specification that uses the config data stored in the ConfigMap:
```yaml
apiVersion: v1
kind: Pod
metadata:
name: redis
spec:
containers:
- name: redis
image: kubernetes/redis:v1
env:
- name: MASTER
value: "true"
ports:
- containerPort: 6379
resources:
limits:
cpu: "0.1"
volumeMounts:
- mountPath: /redis-master-data
name: data
- mountPath: /redis-master
name: config
volumes:
- name: data
emptyDir: {}
- name: config
configMap:
name: example-redis-config
items:
- key: redis-config
path: redis.conf
```
1. Create the pod:
```shell
kubectl create -f docs/user-guide/configmap/redis/redis-pod.yaml
```
In the example, the config volume is mounted at `/redis-master`.
It uses `path` to add the `redis-config` key to a file named `redis.conf`.
The file path for the redis config, therefore, is `/redis-master/redis.conf`.
This is where the image will look for the config file for the redis master.
1. Use `kubectl exec` to enter the pod and run the `redis-cli` tool to verify that the configuration was correctly applied:
```shell
kubectl exec -it redis redis-cli
127.0.0.1:6379> CONFIG GET maxmemory
1) "maxmemory"
2) "2097152"
127.0.0.1:6379> CONFIG GET maxmemory-policy
1) "maxmemory-policy"
2) "allkeys-lru"
```
{% endcapture %}
{% capture whatsnext %}
* Learn more about [ConfigMaps](/docs/tasks/configure-pod-container/configmap/).
* See [Using ConfigMap Data in Pods](/docs/tasks/configure-pod-container/configure-pod-configmap).
{% endcapture %}
{% include templates/tutorial.md %}