Use spaces to separate
diff --git a/files/openstack.cfg b/files/openstack.cfg
index 185cd74..1963ef6 100644
--- a/files/openstack.cfg
+++ b/files/openstack.cfg
@@ -15,19 +15,19 @@
 openstack-dashboard:
    openstack-origin: "cloud:trusty-kilo"
 neutron-gateway:
-   bridge-mappings: "physnet1:br-data,nat:br-nat"
+   bridge-mappings: "physnet1:br-data nat:br-nat"
    flat-network-providers: "*"
    instance-mtu: "1400"
    openstack-origin: "cloud:trusty-kilo"
-   vlan-ranges: "physnet1:1000:2000,nat"
+   vlan-ranges: "physnet1:1000:2000 nat"
 neutron-api:
    flat-network-providers: "*"
    openstack-origin: "cloud:trusty-kilo"
-   vlan-ranges: "physnet1:1000:2000,nat"
+   vlan-ranges: "physnet1:1000:2000 nat"
 neutron-openvswitch:
-   bridge-mappings: "physnet1:br-data,nat:br-nat"
+   bridge-mappings: "physnet1:br-data nat:br-nat"
    disable-security-groups: "True"
    flat-network-providers: "*"
-   vlan-ranges: "physnet1:1000:2000,nat"
+   vlan-ranges: "physnet1:1000:2000 nat"
 rabbitmq-server:
   ssl: "on"