Merge pull request #238 from leakingtapan/readme

Add example for block volume

examples/kubernetes/block-volume/README.md

@@ -0,0 +1,39 @@
+## Raw Block Volume
+This example shows how to consume a dynamically-provisioned EBS 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/specs/pod.yaml

@@ -0,0 +1,17 @@
+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/raw-claim.yaml

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

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

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

examples/kubernetes/pod-single-volume/README.md

@@ -26,4 +26,4 @@ kubectl exec -it app cat /data/out.txt
 4. Cleanup resources:
 ```
 kubectl delete -f specs/
-```
+```