diff --git a/gestion/gen_confs/firewall.py b/gestion/gen_confs/firewall.py
index ef545e50..f565bac0 100755
--- a/gestion/gen_confs/firewall.py
+++ b/gestion/gen_confs/firewall.py
@@ -583,6 +583,9 @@ class firewall_komaz(firewall_crans) :
             # Classification des adhérents dans leur classe respective
             for machine in adherent.machines():
                 ip = machine.ip()
+                if not AddrInNet(ip, NETs['all']):
+                    # Cas particulier d'une machine ayant une IP non CRANS
+                    continue
                 subnet = IpSubnet(machine.ip(), conf_fw.mask[-1])
                 iptables("-t mangle -A SUBNET-%(subnet)s -o crans -d %(ip)s "
                          "-j CLASSIFY --set-class 1:%(class_id)s" % locals())