diff --git a/gns3server/compute/dynamips/nodes/atm_switch.py b/gns3server/compute/dynamips/nodes/atm_switch.py
index 9dd23d2f..deda2c29 100644
--- a/gns3server/compute/dynamips/nodes/atm_switch.py
+++ b/gns3server/compute/dynamips/nodes/atm_switch.py
@@ -287,10 +287,10 @@ class ATMSwitch(Device):
         """
 
         if port1 not in self._nios:
-            raise DynamipsError("Port {} is not allocated".format(port1))
+            return
 
         if port2 not in self._nios:
-            raise DynamipsError("Port {} is not allocated".format(port2))
+            return
 
         nio1 = self._nios[port1]
         nio2 = self._nios[port2]
@@ -322,10 +322,10 @@ class ATMSwitch(Device):
         """
 
         if port1 not in self._nios:
-            raise DynamipsError("Port {} is not allocated".format(port1))
+            return
 
         if port2 not in self._nios:
-            raise DynamipsError("Port {} is not allocated".format(port2))
+            return
 
         nio1 = self._nios[port1]
         nio2 = self._nios[port2]
@@ -359,10 +359,10 @@ class ATMSwitch(Device):
         """
 
         if port1 not in self._nios:
-            raise DynamipsError("Port {} is not allocated".format(port1))
+            return
 
         if port2 not in self._nios:
-            raise DynamipsError("Port {} is not allocated".format(port2))
+            return
 
         nio1 = self._nios[port1]
         nio2 = self._nios[port2]
@@ -400,10 +400,10 @@ class ATMSwitch(Device):
         """
 
         if port1 not in self._nios:
-            raise DynamipsError("Port {} is not allocated".format(port1))
+            return
 
         if port2 not in self._nios:
-            raise DynamipsError("Port {} is not allocated".format(port2))
+            return
 
         nio1 = self._nios[port1]
         nio2 = self._nios[port2]