diff --git a/gestion/gen_confs/firewall.py b/gestion/gen_confs/firewall.py
index 458e858f..c677bf05 100755
--- a/gestion/gen_confs/firewall.py
+++ b/gestion/gen_confs/firewall.py
@@ -79,7 +79,7 @@ class firewall_crans :
           faut pour mettre en place un fw basique n'effectuant que la
           verif MAC-IP.
     """
-    zone_serveur="138.231.136.0/24"
+    zone_serveur="138.231.136.0/28"
     vlan_adm="138.231.144.0/24"
 
     adm_users = [ "root", "identd", "daemon", "postfix", "freerad", "amavis", "nut", "respbats", "list", "sqlgrey"]