[CE-366] Add persistent volume for k8s

Currently ansible agent does not provide persistent
volume for created k8s env. This patch will add that
capability. It will create a nfs based persistent
volume.

Change-Id: I3ec80b04a74b54193cc5b445b4b4024967662d4b
Signed-off-by: Tong Li <litong01@us.ibm.com>

src/agent/ansible/roles/env_k8s/master/tasks/apply.yml

@@ -125,8 +125,6 @@
   template:
     src: "{{ playbook_dir }}/../env_k8s/master/templates/kubeconfig.j2"
     dest: "/etc/kubernetes/kubeconfig"
-    mode: 0600
-  become: false
   tags: "kubeconfig"
 
 - name: Get the kubeconfig to the ansible controller

src/agent/ansible/roles/env_k8s/post/tasks/apply.yml

@@ -20,6 +20,7 @@
   with_items:
     - dnscontroller
     - dashboard
+    - pv
 
 - name: Label the master node
   command: >-
@@ -31,18 +32,29 @@
     {{ fabricroot }}/bin/kubectl --server={{ private_ip }}:8080 create secret generic
     kubernetes-dashboard-certs --from-file=/etc/kubernetes/secrets/certs -n kube-system
 
+- name: Ensure NFS directory exists
+  file:
+    path: /opt/k8spv
+    state: directory
+
+- name: Launch NFS server
+  command: >-
+    docker run -d --name nfs --privileged --net=host
+    -v /opt/k8spv:/nfsshare -e SHARED_DIRECTORY=/nfsshare
+    itsthenetwork/nfs-server-alpine:latest
+
 - name: Create addon services
   command: >-
     {{ fabricroot }}/bin/kubectl --server={{ private_ip }}:8080 apply
     -f /etc/kubernetes/{{ item }}.yaml
   with_items:
     - dnscontroller
     - dashboard
+    - pv
 
 # The following code setup a native docker nginx container to
 # proxy dns lookup to k8s dns services so that containers
 # created by docker containers can also use names
-
 - name: Upload nginx configuration file
   template:
     src: "{{ playbook_dir }}/../env_k8s/post/templates/nginx.j2"

src/agent/ansible/roles/env_k8s/post/templates/pv.j2

@@ -0,0 +1,14 @@
+---
+apiVersion: v1
+kind: PersistentVolume
+metadata:
+  name: k8spv
+spec:
+  capacity:
+    storage: 5Gi
+  accessModes:
+  - ReadWriteOnce
+  nfs:
+    path: /
+    server: {{ private_ip }}
+  persistentVolumeReclaimPolicy: Recycle

src/agent/ansible/roles/env_k8s/worker/tasks/apply.yml

@@ -6,6 +6,10 @@
     service_path: "/lib/systemd/system/"
     fabricroot: "/opt/fabric"
 
+- name: Install nfs-common
+  apt:
+    name: nfs-common
+
 - name: Ensure binary directory exists
   file:
     path: "{{ item }}"