diff --git a/data/grid5000/sites/luxembourg/network_equipments/gw-luxembourg.json b/data/grid5000/sites/luxembourg/network_equipments/gw-luxembourg.json
index f730760ed8679049a1e3142e23968edd1a4a9c34..ced9066d67ea29691c75a95dafcd4bf0a3c3d890 100644
--- a/data/grid5000/sites/luxembourg/network_equipments/gw-luxembourg.json
+++ b/data/grid5000/sites/luxembourg/network_equipments/gw-luxembourg.json
@@ -544,6 +544,7 @@
     }
   ],
   "model": "cisco WS-C6506-E",
+  "mtu": 9216,
   "routes": {
 
   },
diff --git a/data/grid5000/sites/luxembourg/network_equipments/ul-grid5000-sw02.json b/data/grid5000/sites/luxembourg/network_equipments/ul-grid5000-sw02.json
index 54405f0c403aa2c92c3cdc07eba5f576df21d434..a855231cb238ed207e5d93c4bf60984175b8d7c2 100644
--- a/data/grid5000/sites/luxembourg/network_equipments/ul-grid5000-sw02.json
+++ b/data/grid5000/sites/luxembourg/network_equipments/ul-grid5000-sw02.json
@@ -193,6 +193,7 @@
     }
   ],
   "model": "cisco N5K-C5020P-BF",
+  "mtu": 9216,
   "routes": {
 
   },
diff --git a/generators/input/sites/luxembourg/net-links/gw-luxembourg.yaml b/generators/input/sites/luxembourg/net-links/gw-luxembourg.yaml
index 12564295f24fe14c8ccec308fa3ef886fa2d6527..d24b199b566fb98a634111ff5336d3d7a09708a2 100644
--- a/generators/input/sites/luxembourg/net-links/gw-luxembourg.yaml
+++ b/generators/input/sites/luxembourg/net-links/gw-luxembourg.yaml
@@ -5,6 +5,7 @@ gw-luxembourg:
   site: luxembourg
   snmp_community: public
   backplane_bps: 720000000000
+  mtu: 9216
   vlans:
     naming_pattern: Vlan%VLANID%
     "vlan30":
diff --git a/generators/input/sites/luxembourg/net-links/ul-grid5000-sw02.yaml b/generators/input/sites/luxembourg/net-links/ul-grid5000-sw02.yaml
index cbf0863ba04ea8c246d7cb0bba235a15596032e5..93c189801ec5d732e45ac62e19037ee01d3e18a1 100644
--- a/generators/input/sites/luxembourg/net-links/ul-grid5000-sw02.yaml
+++ b/generators/input/sites/luxembourg/net-links/ul-grid5000-sw02.yaml
@@ -5,6 +5,7 @@ ul-grid5000-sw02:
   site: luxembourg
   snmp_community: public
   backplane_bps: 1040000000000
+  mtu: 9216
   weathermap:
     use_cacti: "yes"
   vlans: