Merge pull request #53 from Madhan-SWE/example_workloads

examples added

Author: Power Cloud Robot

example/pod.yaml

@@ -0,0 +1,39 @@
+## Raw Block Volume
+This example shows how to consume a dynamically-provisioned PowerVS volume as a raw block device.
+
+### Edit [Persistence Volume Claim Spec](./specs/raw-claim.yaml)
+Make sure the `volumeMode` is `Block`.
+
+### Edit [Application Pod](./specs/pod.yaml)
+Make sure the pod is consuming the PVC with the defined name and `volumeDevices` is used instead of `volumeMounts`.
+
+### Deploy the Application
+```sh
+kubectl apply -f examples/kubernetes/block-volume/specs/storageclass.yaml
+kubectl apply -f examples/kubernetes/block-volume/specs/raw-claim.yaml
+kubectl apply -f examples/kubernetes/block-volume/specs/pod.yaml
+```
+
+### Access Block Device
+After the objects are created, verify that pod is running:
+
+```sh
+$ kubectl get pods
+NAME   READY   STATUS    RESTARTS   AGE
+app    1/1     Running   0          16m
+```
+Verify the device node is mounted inside the container:
+
+```sh
+$ kubectl exec -ti app -- ls -al /dev/xvda
+brw-rw----    1 root     disk      202, 23296 Mar 12 04:23 /dev/xvda
+```
+
+Write to the device using:
+
+```sh
+dd if=/dev/zero of=/dev/xvda bs=1024k count=100
+100+0 records in
+100+0 records out
+104857600 bytes (105 MB, 100 MiB) copied, 0.0492386 s, 2.1 GB/s
+```

examples/kubernetes/block-volume/Readme.md

@@ -0,0 +1,18 @@
+
+apiVersion: v1
+kind: Pod
+metadata:
+  name: app 
+spec:
+  containers:
+  - name: app 
+    image: busybox 
+    command: ["/bin/sh", "-c"]
+    args: ["tail -f /dev/null"]
+    volumeDevices:
+    - name: data
+      devicePath: /dev/xvda
+  volumes:
+  - name: data
+    persistentVolumeClaim:
+      claimName: block-claim

examples/kubernetes/block-volume/specs/pod.yaml

@@ -0,0 +1,12 @@
+apiVersion: v1
+kind: PersistentVolumeClaim
+metadata:
+  name: block-claim
+spec:
+  accessModes:
+    - ReadWriteOnce
+  volumeMode: Block
+  storageClassName: powervs-sc
+  resources:
+    requests:
+      storage: 10Gi

examples/kubernetes/block-volume/specs/raw-claim.yaml

@@ -0,0 +1,30 @@
+# Dynamic Volume Provisioning
+This example shows how to create a PowerVS volume and consume it from container dynamically.
+
+## Prerequisites
+
+1. Kubernetes 1.13+ (CSI 1.0).
+
+2. The [powervs-ebs-csi-driver](https://github.com/ppc64le-cloud/powervs-csi-driver) is installed.
+
+## Usage
+
+1. Create a sample app along with the StorageClass and the PersistentVolumeClaim:
+```
+kubectl apply -f specs/
+```
+
+2. Validate the volume was created and `volumeHandle` contains an PowerVS volumeID:
+```
+kubectl describe pv
+```
+
+3. Validate the pod successfully wrote data to the volume:
+```
+kubectl exec -it app cat /data/out.txt
+```
+
+4. Cleanup resources:
+```
+kubectl delete -f specs/
+```

example/sc.yaml renamed to examples/kubernetes/block-volume/specs/storageclass.yaml

@@ -8,4 +8,4 @@ spec:
   storageClassName: powervs-sc
   resources:
     requests:
-      storage: 1Gi
+      storage: 4Gi

examples/kubernetes/dynamic-provisioning/Readme.md

@@ -0,0 +1,17 @@
+apiVersion: v1
+kind: Pod
+metadata:
+  name: app
+spec:
+  containers:
+  - name: app
+    image: centos
+    command: ["/bin/sh"]
+    args: ["-c", "while true; do echo $(date -u) >> /data/out.txt; sleep 5; done"]
+    volumeMounts:
+    - name: persistent-storage
+      mountPath: /data
+  volumes:
+  - name: persistent-storage
+    persistentVolumeClaim:
+      claimName: powervs-claim

example/pvc.yaml renamed to examples/kubernetes/dynamic-provisioning/specs/claim.yaml

@@ -0,0 +1,6 @@
+kind: StorageClass
+apiVersion: storage.k8s.io/v1
+metadata:
+  name: powervs-sc
+provisioner: powervs.csi.ibm.com
+volumeBindingMode: WaitForFirstConsumer

examples/kubernetes/dynamic-provisioning/specs/pod.yaml

@@ -0,0 +1,40 @@
+## Volume Resizing
+This example shows how to resize PowerVS persistence volume using volume resizing features.
+
+
+## Usage
+1. Add `allowVolumeExpansion: true` in the StorageClass spec in [example manifest](./spec/example.yaml) to enable volume expansion. You can only expand a PVC if its storage class’s allowVolumeExpansion field is set to true
+
+2. Deploy the example:
+```sh
+kubectl apply -f specs/
+``` 
+
+3. Verify the volume is created and Pod is running:
+```sh
+kubectl get pv
+kubectl get po app
+```
+
+4. Expand the volume size by increasing the capacity in PVC's `spec.resources.requests.storage`:
+```sh
+kubectl edit pvc powervs-claim
+```
+Save the result at the end of the edit.
+
+5. Verify that both the persistence volume and persistence volume claim are resized:
+```sh
+kubectl get pv
+kubectl get pvc
+```
+You should see that both should have the new value relfected in the capacity fields.
+
+6. Verify that the application is continuously running without any interruption:
+```sh
+kubectl exec -it app cat /data/out.txt
+```
+
+7. Cleanup resources:
+```
+kubectl delete -f specs/
+```