diff --git a/labs/config/openstack b/labs/config/openstack
index 55caddec..40367931 100644
--- a/labs/config/openstack
+++ b/labs/config/openstack
@@ -8,5 +8,14 @@
 : ${MGMT_NET:=10.10.10.1}
 : ${DATA_NET:=10.20.20.1}
 : ${API_NET:=192.168.100.1}
+# FIXME API_NET and EXT_NET should be different networks as soon as our
+#       setup allows it.
+: ${EXT_NET:=192.168.100.1}
+
+# EXT_NET
+: ${FLOATING_IP_START:=192.168.100.101}
+: ${FLOATING_IP_END:=192.168.100.200}
+: ${EXTERNAL_NETWORK_GATEWAY:=192.168.100.1}
+: ${EXTERNAL_NETWORK_CIDR:=192.168.100.0/24}
 
 # vim: set ai ts=4 sw=4 et ft=sh:
diff --git a/labs/config/scripts.controller b/labs/config/scripts.controller
index 5988f705..513bfc62 100644
--- a/labs/config/scripts.controller
+++ b/labs/config/scripts.controller
@@ -8,6 +8,7 @@ scripts setup_neutron_controller.sh
 scripts setup_cinder_controller.sh
 scripts setup_cinder_volumes.sh
 scripts setup_horizon.sh
+scripts config_external_network.sh
 scripts shutdown.sh
 boot
 wait_for_shutdown
diff --git a/labs/scripts/config_external_network.sh b/labs/scripts/config_external_network.sh
new file mode 100755
index 00000000..7f52bd7e
--- /dev/null
+++ b/labs/scripts/config_external_network.sh
@@ -0,0 +1,24 @@
+#!/usr/bin/env bash
+TOP_DIR=$(cd $(dirname "$0")/.. && pwd)
+source "$TOP_DIR/config/paths"
+source "$CONFIG_DIR/credentials"
+source "$LIB_DIR/functions.guest"
+source "$CONFIG_DIR/admin-openstackrc.sh"
+exec_logfile
+
+indicate_current_auto
+
+#------------------------------------------------------------------------------
+# Create the external network and a subnet on it.
+#------------------------------------------------------------------------------
+
+echo "Creating the external network."
+neutron net-create ext-net --shared --router:external=True
+
+echo "Creating a subnet on the external network."
+neutron subnet-create ext-net \
+    --name ext-subnet \
+    --allocation-pool start="$FLOATING_IP_START,end=$FLOATING_IP_END" \
+    --disable-dhcp \
+    --gateway "$EXTERNAL_NETWORK_GATEWAY" \
+    "$EXTERNAL_NETWORK_CIDR"