Put moved notice in persistent volume topic.
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steveperry-53
Andrew Chen
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2973296f28
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@ -1,7 +1,4 @@
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---
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redirect_from:
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- "/docs/user-guide/persistent-volumes/walkthrough/"
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- "/docs/user-guide/persistent-volumes/walkthrough.html"
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title: Configuring a Pod to Use a PersistentVolume for Storage
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---
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@ -5,124 +5,6 @@ assignees:
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title: Persistent Volumes Walkthrough
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---
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The purpose of this guide is to help you become familiar with [Kubernetes Persistent Volumes](/docs/user-guide/persistent-volumes/). By the end of the guide, we'll have
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nginx serving content from your persistent volume.
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{% include user-guide-content-moved.md %}
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You can view all the files for this example in [the docs repo
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here](https://github.com/kubernetes/kubernetes.github.io/tree/{{page.docsbranch}}/docs/user-guide/persistent-volumes).
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This guide assumes knowledge of Kubernetes fundamentals and that you have a cluster up and running.
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See [Persistent Storage design document](https://github.com/kubernetes/kubernetes/blob/{{page.githubbranch}}/docs/design/persistent-storage.md) for more information.
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## Provisioning
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A Persistent Volume (PV) in Kubernetes represents a real piece of underlying storage capacity in the infrastructure. Cluster administrators
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must first create storage (create their Google Compute Engine (GCE) disks, export their NFS shares, etc.) in order for Kubernetes to mount it.
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PVs are intended for "network volumes" like GCE Persistent Disks, NFS shares, and AWS ElasticBlockStore volumes. `HostPath` was included
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for ease of development and testing. You'll create a local `HostPath` for this example.
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> IMPORTANT! For `HostPath` to work, you will need to run a single node cluster. Kubernetes does not
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support local storage on the host at this time. There is no guarantee your pod ends up on the correct node where the `HostPath` resides.
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```shell
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# This will be nginx's webroot; execute this on the node where your pod will run.
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$ mkdir /tmp/data01
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$ echo 'I love Kubernetes storage!' > /tmp/data01/index.html
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```
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PVs are created by posting them to the API server.
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```shell
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$ kubectl create -f docs/user-guide/persistent-volumes/volumes/local-01.yaml
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NAME LABELS CAPACITY ACCESSMODES STATUS CLAIM REASON
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pv0001 type=local 10737418240 RWO Available
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```
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### Access Control
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Storage configured with GID will only allow writing by pods using the same GID.
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Mismatched or missing GIDs will cause `permission denied` errors. Annotating a
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`PersistentVolume` with a GID allows `Kubelet` to automatically add the GID to
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the pod that requires it. No coordination between an admin and end user is
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required.
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To annotate the volume's with a GID you use the `pv.beta.kubernetes.io/gid`
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annotation as follows:
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```yaml
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kind: PersistentVolume
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apiVersion: v1
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metadata:
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name: pv1
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annotations:
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pv.beta.kubernetes.io/gid: "1234"
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#...
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```
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When a pod consumes a PV with a GID annotation, the annotated GID is applied to
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all containers in the pod in the same way GIDs specified in the pod's
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[security context](/docs/user-guide/security-context/) are. Every GID, whether
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it originates from a PV annotation or the pod's specification, is applied to
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the first process run in each container, in addition to the container's primary
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GID. Currently, the GIDs associated with PVs a pod consumes will not be present
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on the pod resource itself, unlike GIDs specified in a pod's security context.
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## Requesting storage
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Users of Kubernetes request persistent storage for their pods. They don't know how the underlying cluster is provisioned.
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They just know they can rely on their claim to storage and can manage its lifecycle independently from the many pods that may use it.
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Claims must be created in the same namespace as the pods that use them.
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```shell
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$ kubectl create -f docs/user-guide/persistent-volumes/claims/claim-01.yaml
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$ kubectl get pvc
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NAME LABELS STATUS VOLUME
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myclaim-1 map[]
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# A background process will attempt to match this claim to a volume.
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# The eventual state of your claim will look something like this:
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$ kubectl get pvc
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NAME LABELS STATUS VOLUME
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myclaim-1 map[] Bound pv0001
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$ kubectl get pv
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NAME LABELS CAPACITY ACCESSMODES STATUS CLAIM REASON
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pv0001 type=local 10737418240 RWO Bound default/myclaim-1
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```
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## Using your claim as a volume
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Claims are used as volumes in pods. Kubernetes uses the claim to look up its bound PV. The PV is then exposed to the pod.
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```shell
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$ kubectl create -f docs/user-guide/persistent-volumes/simpletest/pod.yaml
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$ kubectl get pods
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NAME READY STATUS RESTARTS AGE
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mypod 1/1 Running 0 1h
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$ kubectl create -f docs/user-guide/persistent-volumes/simpletest/service.json
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$ kubectl get services
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NAME CLUSTER_IP EXTERNAL_IP PORT(S) SELECTOR AGE
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frontendservice 10.0.0.241 <none> 3000/TCP name=frontendhttp 1d
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kubernetes 10.0.0.2 <none> 443/TCP <none> 2d
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```
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## Next steps
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You should be able to query your service endpoint and see what content nginx is serving. A "forbidden" error might mean you
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need to disable SELinux (setenforce 0).
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```shell
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$ curl 10.0.0.241:3000
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I love Kubernetes storage!
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```
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Hopefully this simple guide is enough to get you started with PersistentVolumes. If you have any questions, join the team on [Slack](/docs/troubleshooting/#slack) and ask!
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Enjoy!
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[Configuring a Pod to Use a Persistent Volume for Storage](/docs/tasks/configure-pod-container/configure-persistent-volume-storage/)
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