diff --git a/tcp_tests/templates/_heat_environments/fragments/Subnets.yaml b/tcp_tests/templates/_heat_environments/fragments/Subnets.yaml
index 2a248cb..b4000e4 100644
--- a/tcp_tests/templates/_heat_environments/fragments/Subnets.yaml
+++ b/tcp_tests/templates/_heat_environments/fragments/Subnets.yaml
@@ -41,9 +41,9 @@
     type: string
   management_subnet_pool_end:
     type: string
-#  external_net_dhcp:
-#    type: boolean
-#    default: false
+  external_net_dhcp:
+    type: boolean
+    default: false
 
   nameservers:
     type: comma_delimited_list
@@ -95,7 +95,7 @@
       name: { list_join: ['-', [ { get_param: external_net }, 'subnet', { get_param: env_name } ]] }
       network: { get_param: external_net }
       cidr: { get_param: external_subnet_cidr }
-      #enable_dhcp: { get_param: external_net_dhcp }
+      enable_dhcp: { get_param: external_net_dhcp }
       dns_nameservers: [0.0.0.0]
       gateway_ip: null
       tags: