Make it possible to skip docker role as a var (#2686)

cluster.yml

@@ -33,7 +33,7 @@
   roles:
     - { role: kubespray-defaults}
     - { role: kubernetes/preinstall, tags: preinstall }
-    - { role: docker, tags: docker }
+    - { role: docker, tags: docker, when: manage_docker|default(true) }
     - role: rkt
       tags: rkt
       when: "'rkt' in [etcd_deployment_type, kubelet_deployment_type, vault_deployment_type]"

roles/kubespray-defaults/defaults/main.yaml

@@ -129,6 +129,10 @@ kube_apiserver_insecure_port: 8080
 # Aggregator
 kube_api_aggregator_routing: false
 
+# Docker options
+# Optionally do not run docker role
+manage_docker: true
+
 # Path used to store Docker data
 docker_daemon_graph: "/var/lib/docker"
 

scale.yml

@@ -28,7 +28,7 @@
   roles:
     - { role: kubespray-defaults}
     - { role: kubernetes/preinstall, tags: preinstall }
-    - { role: docker, tags: docker }
+    - { role: docker, tags: docker, when: manage_docker|default(true) }
     - role: rkt
       tags: rkt
       when: "'rkt' in [etcd_deployment_type, kubelet_deployment_type, vault_deployment_type]"

upgrade-cluster.yml

@@ -34,7 +34,7 @@
   roles:
     - { role: kubespray-defaults}
     - { role: kubernetes/preinstall, tags: preinstall }
-    - { role: docker, tags: docker }
+    - { role: docker, tags: docker, when: manage_docker|default(true) }
     - role: rkt
       tags: rkt
       when: "'rkt' in [etcd_deployment_type, kubelet_deployment_type, vault_deployment_type]"