diff --git a/roles/nat_server/tasks/main.yml b/roles/nat_server/tasks/main.yml
index 1e7fd39b588a527b2c65db2246510e87afea19c8..6c56c0ce8b10d821baee37ebf990ceb3ca82c47d 100644
--- a/roles/nat_server/tasks/main.yml
+++ b/roles/nat_server/tasks/main.yml
@@ -23,6 +23,8 @@
   # output looks like
   # 8.8.8.8 via 118.138.254.254 dev eth2  src 118.138.254.185
   shell: /usr/sbin/ip route get 8.8.8.8  | awk '{print $5;exit }'
+  check_mode: no
+  changed_when: false
   register: public_device_name
 
 #if not defined, default to M3=vlan 114  ;