Write new task: Configuring a Pod to Use a Volume for Storage.

_data/tasks.yml

@@ -3,6 +3,7 @@ abstract: "Step-by-step instructions for performing operations with Kuberentes."
 toc:
 - title: Tasks
   path: /docs/tasks/
+
 - title: Configuring Pods and Containers
   section:
   - title: Defining Environment Variables for a Container
@@ -11,18 +12,19 @@ toc:
     path: /docs/tasks/configure-pod-container/define-command-argument-container/
   - title: Assigning CPU and RAM Resources to a Container
     path: /docs/tasks/configure-pod-container/assign-cpu-ram-container/
+  - title: Configuring a Pod to Use a Volume for Storage
+    path: /docs/tasks/configure-pod-container/configure-volume-storage/
+
 - title: Accessing Applications in a Cluster
   section:
   - title: Using Port Forwarding to Access Applications in a Cluster
     path: /docs/tasks/access-application-cluster/port-forward-access-application-cluster/
 
-
 - title: Debugging Applications in a Cluster
   section:
   - title: Determining the Reason for Pod Failure
     path: /docs/tasks/debug-application-cluster/determine-reason-pod-failure/
 
-
 - title: Accessing the Kubernetes API
   section:
   - title: Using an HTTP Proxy to Access the Kubernetes API
@@ -54,3 +56,5 @@ toc:
   section:
   - title: Debugging Init Containers
     path: /docs/tasks/troubleshoot/debug-init-containers/
+  - title: Configuring Access Control and Identity Management
+    path: /docs/tasks/administer-cluster/access-control-identity-management/

docs/tasks/configure-pod-container/configure-volume-storage.md

@@ -0,0 +1,109 @@
+---
+---
+
+{% capture overview %}
+
+This page shows how to configure a Pod to use a Volume for storage.
+
+A Container's file system lives only as long as the Container does, so when a
+Container terminates and restarts, changes to the filesystem are lost. For more
+consistent storage that is independent of the Container, you can use a
+[Volume](/docs/user-guide/volumes). This is especially important for stateful
+applications, such as key-value stores and databases. For example, Redis is a
+key-value cache and store.
+
+{% endcapture %}
+
+{% capture prerequisites %}
+
+{% include task-tutorial-prereqs.md %}
+
+{% endcapture %}
+
+{% capture steps %}
+
+### Configuring a volume for a Pod
+
+In this exercise, you create a Pod that runs one Container. This Pod has a
+Volume of type
+[emptyDir](/docs/user-guide/volumes/#emptydir)
+that lasts for the life of the Pod, even if the Container terminates and
+restarts. Here is the configuration file for the Pod:
+
+{% include code.html language="yaml" file="pod-redis.yaml" ghlink="/docs/tasks/configure-pod-container/pod-redis.yaml" %}
+
+1. Create the Pod:
+
+        kubectl create -f http://k8s.io/docs/tasks/configure-pod-container/pod-redis.yaml
+
+1. Verify that the Pod's Container is running, and then watch for changes to
+the Pod:
+
+        kubectl get --watch pod redis
+
+    The output looks like this:
+
+        NAME      READY     STATUS    RESTARTS   AGE
+        redis     1/1       Running   0          13s
+
+1. In another terminal, get a shell to the running Container:
+
+        kubectl exec -it redis -- /bin/bash
+
+1. In your shell, go to `/data/redis`, and create a file:
+
+        root@redis:/data/redis# echo Hello > test-file
+
+1. In your shell, list the running processes:
+
+        root@redis:/data/redis# ps aux
+
+    The output is similar to this:
+
+        USER       PID %CPU %MEM    VSZ   RSS TTY      STAT START   TIME COMMAND
+        redis        1  0.1  0.1  33308  3828 ?        Ssl  00:46   0:00 redis-server *:6379
+        root        12  0.0  0.0  20228  3020 ?        Ss   00:47   0:00 /bin/bash
+        root        15  0.0  0.0  17500  2072 ?        R+   00:48   0:00 ps aux
+
+1. In your shell, kill the redis process:
+
+        root@redis:/data/redis# kill <pid>
+
+    where `<pid>` is the redis process ID (PID).
+
+1. In your original terminal, watch for changes to the redis Pod. Eventually,
+you will see something like this:
+
+        NAME      READY     STATUS     RESTARTS   AGE
+        redis     1/1       Running    0          13s
+        redis     0/1       Completed  0         6m
+        redis     1/1       Running    1         6m
+
+At this point, the Container has terminated and restarted. This is because the
+redis Pod has a
+[restartPolicy](http://kubernetes.io/docs/api-reference/v1/definitions#_v1_podspec)
+of `Always`.
+
+1. Get a shell into the restarted Container:
+
+        kubectl exec -it redis -- /bin/bash
+
+1. In your shell, goto `/data/redis`, and verify that `test-file` is still there.
+
+{% endcapture %}
+
+{% capture whatsnext %}
+
+* See [Volume](/docs/api-reference/v1/definitions/#_v1_volume).
+
+* See [Pod](http://kubernetes.io/docs/api-reference/v1/definitions#_v1_pod).
+
+* In addition to the local disk storage provided by `emptyDir`, Kubernetes
+supports many different network-attached storage solutions, including PD on
+GCE and EBS on EC2, which are preferred for critical data, and will handle
+details such as mounting and unmounting the devices on the nodes. See
+[Volumes](/docs/user-guide/volumes) for more details.
+
+{% endcapture %}
+
+{% include templates/task.md %}

docs/tasks/configure-pod-container/pod-redis.yaml

@@ -0,0 +1,14 @@
+apiVersion: v1
+kind: Pod
+metadata:
+  name: redis
+spec:
+  containers:
+  - name: redis
+    image: redis
+    volumeMounts:
+    - name: redis-storage
+      mountPath: /data/redis
+  volumes:
+  - name: redis-storage
+    emptyDir: {}