diff --git a/tools/init-runonce b/tools/init-runonce
index 336baa162d..54708ac1ea 100755
--- a/tools/init-runonce
+++ b/tools/init-runonce
@@ -15,6 +15,7 @@ IMAGE_NAME=cirros
 IMAGE_TYPE=linux
 
 # This EXT_NET_CIDR is your public network,that you want to connect to the internet via.
+ENABLE_EXT_NET=${ENABLE_EXT_NET:-1}
 EXT_NET_CIDR='10.0.2.0/24'
 EXT_NET_RANGE='start=10.0.2.150,end=10.0.2.199'
 EXT_NET_GATEWAY='10.0.2.1'
@@ -66,11 +67,13 @@ openstack image create --disk-format qcow2 --container-format bare --public \
     --property os_type=${IMAGE_TYPE} --file ${IMAGE_PATH}/${IMAGE} ${IMAGE_NAME}
 
 echo Configuring neutron.
-openstack network create --external --provider-physical-network physnet1 \
-    --provider-network-type flat public1
-openstack subnet create --no-dhcp \
-    --allocation-pool ${EXT_NET_RANGE} --network public1 \
-    --subnet-range ${EXT_NET_CIDR} --gateway ${EXT_NET_GATEWAY} public1-subnet
+if [[ $ENABLE_EXT_NET -eq 1 ]]; then
+    openstack network create --external --provider-physical-network physnet1 \
+        --provider-network-type flat public1
+    openstack subnet create --no-dhcp \
+        --allocation-pool ${EXT_NET_RANGE} --network public1 \
+        --subnet-range ${EXT_NET_CIDR} --gateway ${EXT_NET_GATEWAY} public1-subnet
+fi
 
 openstack network create --provider-network-type vxlan demo-net
 openstack subnet create --subnet-range 10.0.0.0/24 --network demo-net \
@@ -78,7 +81,9 @@ openstack subnet create --subnet-range 10.0.0.0/24 --network demo-net \
 
 openstack router create demo-router
 openstack router add subnet demo-router demo-subnet
-openstack router set --external-gateway public1 demo-router
+if [[ $ENABLE_EXT_NET -eq 1 ]]; then
+  openstack router set --external-gateway public1 demo-router
+fi
 
 # Get admin user and tenant IDs
 ADMIN_USER_ID=$(openstack user list | awk '/ admin / {print $2}')