Add main body to storage _index.md

Adds content for the local path provisoner bundled with k3s and Longhorn.
Each exaplains the essentials to create a pvc and a pod that utilizes it.
This commit is contained in:
David Nuzik
2019-11-10 16:16:25 -07:00
parent ea9d648aa1
commit 6427f8aa80
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@@ -3,4 +3,120 @@ title: "Volumes and Storage"
weight: 30
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Placeholder
When deploying an application that needs to retain data, you’ll need to create persistent storage. Persistent storage allows you to store application data external from the pod running your application. This storage practice allows you to maintain application data, even if the application’s pod fails.
# Local Storage Provider
k3s comes with Rancher's Local Path Provisioner and this enables the ability to create persistent volume claims out of the box using local storage on the respective node. Below we cover a simple example. For more information please reference the official documentation [here](https://github.com/rancher/local-path-provisioner/blob/master/README.md#usage).
Create a hostPath backed persistent volume and a pod to utilize it:
### pvc.yaml
```
apiVersion: v1
kind: PersistentVolumeClaim
metadata:
name: local-path-pvc
namespace: default
spec:
accessModes:
- ReadWriteOnce
storageClassName: local-path
resources:
requests:
storage: 2Gi
```
### pod.yaml
```
apiVersion: v1
kind: Pod
metadata:
name: volume-test
namespace: default
spec:
containers:
- name: volume-test
image: nginx:stable-alpine
imagePullPolicy: IfNotPresent
volumeMounts:
- name: volv
mountPath: /data
ports:
- containerPort: 80
volumes:
- name: volv
persistentVolumeClaim:
claimName: local-path-pvc
```
Apply the yaml `kubectl create -f pvc.yaml` and `kubectl create -f pod.yaml`
Confirm the pv and pvc are created. `kubectl get pv` and `kubectl get pvc` The status should be Bound for each.
# Longhorn
[comment]: <> (pending change - longhorn may support arm64 and armhf in the future.)
> **Note:** At this time Longhorn only supports amd64.
k3s supports [Longhorn](https://github.com/longhorn/longhorn). Below we cover a simple example. For more information please reference the official documentation [here](https://github.com/longhorn/longhorn/blob/master/README.md).
Apply the longhorn.yaml to install Longhorn.
```
kubectl apply -f https://raw.githubusercontent.com/longhorn/longhorn/master/deploy/longhorn.yaml
```
Longhorn will be installed in the namespace `longhorn-system`
Before we create a PVC, we will create a storage class for longhorn with this yaml.
```
kubectl create -f https://raw.githubusercontent.com/longhorn/longhorn/master/examples/storageclass.yaml
```
Now, apply the following yaml to create the pvc and pod with `kubectl create -f pvc.yaml` and `kubectl create -f pod.yaml`
### pvc.yaml
```
apiVersion: v1
kind: PersistentVolumeClaim
metadata:
name: longhorn-volv-pvc
spec:
accessModes:
- ReadWriteOnce
storageClassName: longhorn
resources:
requests:
storage: 2Gi
```
### pod.yaml
```
apiVersion: v1
kind: Pod
metadata:
name: volume-test
namespace: default
spec:
containers:
- name: volume-test
image: nginx:stable-alpine
imagePullPolicy: IfNotPresent
volumeMounts:
- name: volv
mountPath: /data
ports:
- containerPort: 80
volumes:
- name: volv
persistentVolumeClaim:
claimName: longhorn-volv-pvc
```
Confirm the pv and pvc are created. `kubectl get pv` and `kubectl get pvc` The status should be Bound for each.