diff --git a/rally-jobs/extra/autoscaling_group.yaml.template b/rally-jobs/extra/autoscaling_group.yaml.template
index 6c9892b4..02b9b11a 100644
--- a/rally-jobs/extra/autoscaling_group.yaml.template
+++ b/rally-jobs/extra/autoscaling_group.yaml.template
@@ -8,7 +8,7 @@ parameters:
       - custom_constraint: nova.flavor
   image:
     type: string
-    default: cirros-0.3.5-x86_64-disk
+    default: cirros-0.4.0-x86_64-disk
     constraints:
       - custom_constraint: glance.image
   scaling_adjustment:
@@ -30,6 +30,8 @@ resources:
         properties:
             image: { get_param: image }
             flavor: { get_param: flavor }
+            networks:
+              - allocate_network: none
       min_size: 1
       desired_capacity: 3
       max_size: { get_param: max_size }
diff --git a/rally-jobs/extra/resource_group_server_with_volume.yaml.template b/rally-jobs/extra/resource_group_server_with_volume.yaml.template
index 31f87cca..5ad32920 100644
--- a/rally-jobs/extra/resource_group_server_with_volume.yaml.template
+++ b/rally-jobs/extra/resource_group_server_with_volume.yaml.template
@@ -14,7 +14,7 @@ parameters:
       - range: {min: 1}
   instance_image:
     type: string
-    default: cirros-0.3.5-x86_64-disk
+    default: cirros-0.4.0-x86_64-disk
   instance_volume_size:
     type: number
     description: Size of volume to attach to instance
diff --git a/rally-jobs/extra/server_with_ports.yaml.template b/rally-jobs/extra/server_with_ports.yaml.template
index 0e344fc0..ded4835e 100644
--- a/rally-jobs/extra/server_with_ports.yaml.template
+++ b/rally-jobs/extra/server_with_ports.yaml.template
@@ -7,7 +7,7 @@ parameters:
     default: public
   image:
     type: string
-    default: cirros-0.3.5-x86_64-disk
+    default: cirros-0.4.0-x86_64-disk
   flavor:
     type: string
     default: m1.tiny
diff --git a/rally-jobs/extra/server_with_volume.yaml.template b/rally-jobs/extra/server_with_volume.yaml.template
index 6e65cec7..464759ab 100644
--- a/rally-jobs/extra/server_with_volume.yaml.template
+++ b/rally-jobs/extra/server_with_volume.yaml.template
@@ -4,7 +4,7 @@ parameters:
   # set all correct defaults for parameters before launch test
   image:
     type: string
-    default: cirros-0.3.5-x86_64-disk
+    default: cirros-0.4.0-x86_64-disk
   flavor:
     type: string
     default: m1.tiny
@@ -26,6 +26,8 @@ resources:
     properties:
       image: {get_param: image}
       flavor: {get_param: flavor}
+      networks:
+        - allocate_network: none
   cinder_volume:
     type: OS::Cinder::Volume
     properties:
diff --git a/rally-jobs/senlin.yaml b/rally-jobs/senlin.yaml
index 4d634f78..5fa3e096 100644
--- a/rally-jobs/senlin.yaml
+++ b/rally-jobs/senlin.yaml
@@ -25,6 +25,6 @@
           properties:
             name: cirros_server
             flavor: 1
-            image: "cirros-0.3.5-x86_64-disk"
+            image: "cirros-0.4.0-x86_64-disk"
             networks:
               - network: private
diff --git a/rally_openstack/scenarios/heat/utils.py b/rally_openstack/scenarios/heat/utils.py
index a2a7ae6d..a3fb8cec 100644
--- a/rally_openstack/scenarios/heat/utils.py
+++ b/rally_openstack/scenarios/heat/utils.py
@@ -325,8 +325,8 @@ class HeatScenario(scenario.OpenStackScenario):
                 {"key": output_key, "id": stack.id})
 
         platform_params = self.context["env"]["spec"]["existing@openstack"]
-        verify = (platform_params["https_cacert"]
-                  if not platform_params["https_insecure"]
+        verify = (platform_params.get("https_cacert")
+                  if not platform_params.get("https_insecure")
                   else False)
         with atomic.ActionTimer(self, "heat.%s_webhook" % output_key):
             requests.post(url, verify=verify).raise_for_status()