Install Kubernetes 1.11 and go back to Ubuntu Xenial until Bionic is officially supported

roles/kubernetes/tasks/cni.yml

@@ -0,0 +1,40 @@
+---
+# flannel deployment
+- name: Checking if flannel exists
+  shell: "ip link | awk '$2 ~ /^(flannel|cni)/ { print $0 }' | wc -l | awk '{ print $1 }'"
+  register: cni_deployment
+  changed_when: False
+  check_mode: False
+
+- block:
+    - name: Determine physical interface to use with cni
+      shell: "ip route get 169.254.42.42 | head -n1 | sed -E 's/.+ dev ([^ ]+).+/\\1/'"
+      register: cni_interface
+      changed_when: False
+      check_mode: False
+      failed_when: "cni_interface.stdout is not match('^[a-z][a-z0-9]+$')"
+
+    - name: Create directories
+      file:
+        path: "{{ item }}"
+        state: directory
+        mode: 0755
+      with_items:
+        - /etc/kube-flannel
+        - /etc/cni/net.d
+        - /opt/cni/bin
+
+    - template:
+        src: kube-flannel.yml.j2
+        dest: /tmp/kube-flannel.yml
+
+    - name: Configure cni
+      shell: "kubectl apply -f /tmp/kube-flannel.yml"
+      register: cni_output
+      # flannel has trouble unless we restart the kubelet service
+      # we'll flush_handlers later
+      notify: restart kubelet
+
+    - debug: var="cni_output"
+
+  when: "cni_deployment.stdout != '2'"