diff --git a/gns3server/modules/base.py b/gns3server/modules/base.py
index ff80143d..2c8105be 100644
--- a/gns3server/modules/base.py
+++ b/gns3server/modules/base.py
@@ -22,6 +22,7 @@ Base class (interface) for modules
 import gns3server.jsonrpc as jsonrpc
 import multiprocessing
 import zmq
+import signal
 
 import logging
 log = logging.getLogger(__name__)
@@ -101,6 +102,13 @@ class IModule(multiprocessing.Process):
         Starts the event loop
         """
 
+        def signal_handler(signum=None, frame=None):
+            log.warning("Module {} got signal {}, exiting...".format(self.name, signum))
+            self.stop()
+
+        for sig in [signal.SIGTERM, signal.SIGINT, signal.SIGHUP, signal.SIGQUIT]:
+            signal.signal(sig, signal_handler)
+
         log.info("{} module running with PID {}".format(self.name, self.pid))
         self._setup()
         try:
@@ -113,7 +121,8 @@ class IModule(multiprocessing.Process):
         Stops the event loop.
         """
 
-        self._ioloop.stop()
+        if self._ioloop:
+            self._ioloop.stop()
 
     def send_response(self, results):
         """
diff --git a/gns3server/modules/dynamips/__init__.py b/gns3server/modules/dynamips/__init__.py
index 531ce361..ede4b8b0 100644
--- a/gns3server/modules/dynamips/__init__.py
+++ b/gns3server/modules/dynamips/__init__.py
@@ -105,9 +105,11 @@ class Dynamips(IModule):
         self._atm_switches = {}
         self._ethernet_hubs = {}
 
-#     def __del__(self):
-# 
-#         self._hypervisor_manager.stop_all_hypervisors()
+    def stop(self):
+
+        if self._hypervisor_manager:
+            self._hypervisor_manager.stop_all_hypervisors()
+        IModule.stop(self)
 
     @IModule.route("dynamips.reset")
     def reset(self, request):
@@ -153,7 +155,6 @@ class Dynamips(IModule):
         :param request: JSON request
         """
 
-        print("Create")
         if not self._hypervisor_manager:
             self._hypervisor_manager = HypervisorManager(request["path"], "/tmp")
 
@@ -183,6 +184,11 @@ class Dynamips(IModule):
             rhost = request["rhost"]
             rport = request["rport"]
             nio = NIO_UDP(node.hypervisor, lport, rhost, rport)
+#         elif request["nio"] == "NIO_UDP_Auto":
+#             lhost = request["lhost"]
+#             lport_start = request["lport_start"]
+#             lport_end = request["lport_end"]
+#             nio = NIO_UDP_auto(node.hypervisor, lhost, lport_start, lport_end)
         elif request["nio"] == "NIO_GenericEthernet":
             ethernet_device = request["ethernet_device"]
             nio = NIO_GenericEthernet(node.hypervisor, ethernet_device)
@@ -223,6 +229,20 @@ class Dynamips(IModule):
 
         return response
 
+#     def allocate_udp_port_auto(self, node, lport_start, lport_end):
+#         """
+#         Allocates a UDP port in order to create an UDP NIO Auto.
+# 
+#         :param node: the node that needs to allocate an UDP port
+#         """
+# 
+#         self._nio_udp_auto = NIO_UDP_auto(node.hypervisor, node.hypervisor.host, lport_start, lport_end)
+# 
+#         response = {"lport": self._nio_udp_auto.lport,
+#                     "lhost": self._nio_udp_auto.lhost}
+# 
+#         return response
+
     def set_ghost_ios(self, router):
 
         if not router.mmap:
@@ -249,8 +269,9 @@ class Dynamips(IModule):
             ghost.stop()
             ghost.delete()
 
-        router.ghost_status = 2
-        router.ghost_file = ghost_instance
+        if router.ghost_file != ghost_instance:
+            router.ghost_status = 2
+            router.ghost_file = ghost_instance
 
     @IModule.route("dynamips.nio.get_interfaces")
     def nio_get_interfaces(self, request):
diff --git a/gns3server/modules/dynamips/backends/atmsw.py b/gns3server/modules/dynamips/backends/atmsw.py
index 4479c2c3..26428d1d 100644
--- a/gns3server/modules/dynamips/backends/atmsw.py
+++ b/gns3server/modules/dynamips/backends/atmsw.py
@@ -39,7 +39,7 @@ class ATMSW(object):
             name = request["name"]
 
         try:
-            hypervisor = self._hypervisor_manager.allocate_hypervisor_for_switch()
+            hypervisor = self._hypervisor_manager.allocate_hypervisor_for_simulated_device()
             atmsw = ATMSwitch(hypervisor, name)
         except DynamipsError as e:
             self.send_custom_error(str(e))
@@ -65,6 +65,7 @@ class ATMSW(object):
         atmsw = self._atm_switches[atmsw_id]
         try:
             atmsw.delete()
+            self._hypervisor_manager.unallocate_hypervisor_for_simulated_device(atmsw)
         except DynamipsError as e:
             self.send_custom_error(str(e))
             return
@@ -105,6 +106,7 @@ class ATMSW(object):
             self.send_custom_error(str(e))
             return
 
+        response["port_name"] = request["port_name"]
         self.send_response(response)
 
     @IModule.route("dynamips.atmsw.add_nio")
@@ -121,7 +123,7 @@ class ATMSW(object):
         atmsw = self._atm_switches[atmsw_id]
 
         port = request["port"]
-        mapping = request["mapping"]
+        mappings = request["mappings"]
 
         try:
             nio = self.create_nio(atmsw, request)
@@ -132,7 +134,7 @@ class ATMSW(object):
         try:
             atmsw.add_nio(nio, port)
             pvc_entry = re.compile(r"""^([0-9]*):([0-9]*):([0-9]*)$""")
-            for source, destination in mapping.items():
+            for source, destination in mappings.items():
                 match_source_pvc = pvc_entry.search(source)
                 match_destination_pvc = pvc_entry.search(destination)
                 if match_source_pvc and match_destination_pvc:
diff --git a/gns3server/modules/dynamips/backends/ethhub.py b/gns3server/modules/dynamips/backends/ethhub.py
index 6060dede..192c2483 100644
--- a/gns3server/modules/dynamips/backends/ethhub.py
+++ b/gns3server/modules/dynamips/backends/ethhub.py
@@ -38,7 +38,7 @@ class ETHHUB(object):
             name = request["name"]
 
         try:
-            hypervisor = self._hypervisor_manager.allocate_hypervisor_for_switch()
+            hypervisor = self._hypervisor_manager.allocate_hypervisor_for_simulated_device()
             ethhub = Hub(hypervisor, name)
         except DynamipsError as e:
             self.send_custom_error(str(e))
@@ -64,6 +64,7 @@ class ETHHUB(object):
         ethhub = self._ethernet_hubs[ethhub_id]
         try:
             ethhub.delete()
+            self._hypervisor_manager.unallocate_hypervisor_for_simulated_device(ethhub)
         except DynamipsError as e:
             self.send_custom_error(str(e))
             return
@@ -106,6 +107,7 @@ class ETHHUB(object):
             self.send_custom_error(str(e))
             return
 
+        response["port_name"] = request["port_name"]
         self.send_response(response)
 
     @IModule.route("dynamips.ethhub.add_nio")
diff --git a/gns3server/modules/dynamips/backends/ethsw.py b/gns3server/modules/dynamips/backends/ethsw.py
index 490fcbae..a56d1f9b 100644
--- a/gns3server/modules/dynamips/backends/ethsw.py
+++ b/gns3server/modules/dynamips/backends/ethsw.py
@@ -38,7 +38,7 @@ class ETHSW(object):
             name = request["name"]
 
         try:
-            hypervisor = self._hypervisor_manager.allocate_hypervisor_for_switch()
+            hypervisor = self._hypervisor_manager.allocate_hypervisor_for_simulated_device()
             ethsw = EthernetSwitch(hypervisor, name)
         except DynamipsError as e:
             self.send_custom_error(str(e))
@@ -64,6 +64,7 @@ class ETHSW(object):
         ethsw = self._ethernet_switches[ethsw_id]
         try:
             ethsw.delete()
+            self._hypervisor_manager.unallocate_hypervisor_for_simulated_device(ethsw)
         except DynamipsError as e:
             self.send_custom_error(str(e))
             return
@@ -116,6 +117,7 @@ class ETHSW(object):
             self.send_custom_error(str(e))
             return
 
+        response["port_name"] = request["port_name"]
         self.send_response(response)
 
     @IModule.route("dynamips.ethsw.add_nio")
diff --git a/gns3server/modules/dynamips/backends/frsw.py b/gns3server/modules/dynamips/backends/frsw.py
index 99245172..260384d0 100644
--- a/gns3server/modules/dynamips/backends/frsw.py
+++ b/gns3server/modules/dynamips/backends/frsw.py
@@ -38,7 +38,7 @@ class FRSW(object):
             name = request["name"]
 
         try:
-            hypervisor = self._hypervisor_manager.allocate_hypervisor_for_switch()
+            hypervisor = self._hypervisor_manager.allocate_hypervisor_for_simulated_device()
             frsw = FrameRelaySwitch(hypervisor, name)
         except DynamipsError as e:
             self.send_custom_error(str(e))
@@ -64,6 +64,7 @@ class FRSW(object):
         frsw = self._frame_relay_switches[frsw_id]
         try:
             frsw.delete()
+            self._hypervisor_manager.unallocate_hypervisor_for_simulated_device(frsw)
         except DynamipsError as e:
             self.send_custom_error(str(e))
             return
@@ -104,6 +105,7 @@ class FRSW(object):
             self.send_custom_error(str(e))
             return
 
+        response["port_name"] = request["port_name"]
         self.send_response(response)
 
     @IModule.route("dynamips.frsw.add_nio")
@@ -120,7 +122,7 @@ class FRSW(object):
         frsw = self._frame_relay_switches[frsw_id]
 
         port = request["port"]
-        mapping = request["mapping"]
+        mappings = request["mappings"]
 
         try:
             nio = self.create_nio(frsw, request)
@@ -132,7 +134,7 @@ class FRSW(object):
             frsw.add_nio(nio, port)
 
             # add the VCs mapped with this port/nio
-            for source, destination in mapping.items():
+            for source, destination in mappings.items():
                 source_port, source_dlci = map(int, source.split(':'))
                 destination_port, destination_dlci = map(int, destination.split(':'))
                 if frsw.has_port(destination_port):
diff --git a/gns3server/modules/dynamips/backends/vm.py b/gns3server/modules/dynamips/backends/vm.py
index 27adf0a4..10ddb2af 100644
--- a/gns3server/modules/dynamips/backends/vm.py
+++ b/gns3server/modules/dynamips/backends/vm.py
@@ -99,18 +99,27 @@ class VM(object):
             log.debug("received request {}".format(request))
 
             #TODO: JSON schema validation
-            #name = request["name"]
+            name = None
+            if "name" in request:
+                name = request["name"]
             platform = request["platform"]
             image = request["image"]
             ram = request["ram"]
 
             try:
                 hypervisor = self._hypervisor_manager.allocate_hypervisor_for_router(image, ram)
-                router = PLATFORMS[platform](hypervisor)
+
+                router = PLATFORMS[platform](hypervisor, name)
                 router.ram = ram
                 router.image = image
                 router.sparsemem = self._hypervisor_manager.sparse_memory_support
                 router.mmap = self._hypervisor_manager.mmap_support
+                if "console" in request:
+                    router.console = request["console"]
+                if "aux" in request:
+                    router.aux = request["aux"]
+                if "mac_addr" in request:
+                    router.mac_addr = request["mac_addr"]
 
                 # JIT sharing support
                 if self._hypervisor_manager.jit_sharing_support:
@@ -161,6 +170,7 @@ class VM(object):
         router = self._routers[router_id]
         try:
             router.delete()
+            self._hypervisor_manager.unallocate_hypervisor_for_router(router)
         except DynamipsError as e:
             self.send_custom_error(str(e))
             return
@@ -223,6 +233,27 @@ class VM(object):
             return
         self.send_response(request)
 
+    @IModule.route("dynamips.vm.reload")
+    def vm_reload(self, request):
+        """
+        Reloads a VM (router)
+
+        :param request: JSON request
+        """
+
+        #TODO: JSON schema validation for the request
+        log.debug("received request {}".format(request))
+        router_id = request["id"]
+        router = self._routers[router_id]
+        try:
+            if router.get_status() != "inactive":
+                router.stop()
+            router.start()
+        except DynamipsError as e:
+            self.send_custom_error(str(e))
+            return
+        self.send_response(request)
+
     @IModule.route("dynamips.vm.update")
     def vm_update(self, request):
         """
@@ -286,6 +317,34 @@ class VM(object):
         # for now send back the original request
         self.send_response(request)
 
+    @IModule.route("dynamips.vm.idlepcs")
+    def vm_idlepcs(self, request):
+        """
+        Get idle-pc proposals.
+
+        :param request: JSON request
+        """
+
+        #TODO: JSON schema validation for the request
+        log.debug("received request {}".format(request))
+        router_id = request["id"]
+        router = self._routers[router_id]
+
+        try:
+            if "compute" in request and request["compute"] == False:
+                idlepcs = router.show_idle_pc_prop()
+            else:
+                # reset the current idlepc value
+                router.idlepc = "0x0"
+                idlepcs = router.get_idle_pc_prop()
+        except DynamipsError as e:
+            self.send_custom_error(str(e))
+            return
+
+        response = {"id": router_id,
+                    "idlepcs": idlepcs}
+        self.send_response(response)
+
     @IModule.route("dynamips.vm.allocate_udp_port")
     def vm_allocate_udp_port(self, request):
         """
@@ -306,6 +365,7 @@ class VM(object):
             self.send_custom_error(str(e))
             return
 
+        response["port_name"] = request["port_name"]
         self.send_response(response)
 
     @IModule.route("dynamips.vm.add_nio")
@@ -324,8 +384,6 @@ class VM(object):
         slot = request["slot"]
         port = request["port"]
 
-        print(request)
-
         try:
             nio = self.create_nio(router, request)
         except DynamipsError as e:
diff --git a/gns3server/modules/dynamips/hypervisor_manager.py b/gns3server/modules/dynamips/hypervisor_manager.py
index ebb27b33..9eadf034 100644
--- a/gns3server/modules/dynamips/hypervisor_manager.py
+++ b/gns3server/modules/dynamips/hypervisor_manager.py
@@ -401,23 +401,30 @@ class HypervisorManager(object):
         :param timeout: timeout value (default is 10 seconds)
         """
 
-        # try to connect 5 times
-        for _ in range(0, 5):
+        connection_success = False
+        begin = time.time()
+        # try to connect for 10 seconds
+        while(time.time() - begin < 10.0):
+            time.sleep(0.01)
+            sock = None
             try:
-                s = socket.create_connection((host, port), timeout)
+                sock = socket.create_connection((host, port), timeout)
             except socket.error as e:
-                time.sleep(0.5)
                 last_exception = e
+                #time.sleep(0.01)
                 continue
+            finally:
+                if sock:
+                    sock.close()
             connection_success = True
             break
 
-        if connection_success:
-            s.close()
-            #time.sleep(0.1)
-        else:
+        if not connection_success:
+            # FIXME: throw exception here
             log.critical("Couldn't connect to hypervisor on {}:{} :{}".format(host, port,
                                                                              last_exception))
+        else:
+            log.info("Dynamips server ready after {:.4f} seconds".format(time.time() - begin))
 
     def start_new_hypervisor(self):
         """
@@ -501,9 +508,9 @@ class HypervisorManager(object):
             hypervisor.stop()
             self._hypervisors.remove(hypervisor)
 
-    def allocate_hypervisor_for_switch(self):
+    def allocate_hypervisor_for_simulated_device(self):
         """
-        Allocates a Dynamips hypervisor for a specific switch
+        Allocates a Dynamips hypervisor for a specific Dynamips simulated device.
 
         :returns: the allocated hypervisor object
         """
@@ -517,6 +524,18 @@ class HypervisorManager(object):
         # no hypervisor, let's start one!
         return self.start_new_hypervisor()
 
+    def unallocate_hypervisor_for_simulated_device(self, device):
+        """
+        Unallocates a Dynamips hypervisor for a specific Dynamips simulated device.
+
+        :param device: device object
+        """
+
+        hypervisor = device.hypervisor
+        if not hypervisor.devices:
+            hypervisor.stop()
+            self._hypervisors.remove(hypervisor)
+
     def stop_all_hypervisors(self):
         """
         Stops all hypervisors.
diff --git a/gns3server/modules/dynamips/nodes/atm_switch.py b/gns3server/modules/dynamips/nodes/atm_switch.py
index a428b5eb..b68dea6a 100644
--- a/gns3server/modules/dynamips/nodes/atm_switch.py
+++ b/gns3server/modules/dynamips/nodes/atm_switch.py
@@ -35,6 +35,7 @@ class ATMSwitch(object):
     :param name: name for this switch
     """
 
+    _allocated_names = []
     _instance_count = 1
 
     def __init__(self, hypervisor, name=None):
@@ -45,8 +46,15 @@ class ATMSwitch(object):
 
         # let's create a unique name if none has been chosen
         if not name:
-            name = "ATM" + str(self._id)
+            name_id = self._id
+            while True:
+                name = "ATM" + str(name_id)
+                # check if the name has already been allocated to another switch
+                if name not in self._allocated_names:
+                    break
+                name_id += 1
 
+        self._allocated_names.append(name)
         self._hypervisor = hypervisor
         self._name = '"' + name + '"'  # put name into quotes to protect spaces
         self._hypervisor.send("atmsw create {}".format(self._name))
@@ -61,10 +69,11 @@ class ATMSwitch(object):
     @classmethod
     def reset(cls):
         """
-        Reset the instance count.
+        Resets the instance count and the allocated names list.
         """
 
         cls._instance_count = 1
+        cls._allocated_names.clear()
 
     @property
     def id(self):
@@ -94,6 +103,7 @@ class ATMSwitch(object):
         :param new_name: New name for this switch
         """
 
+        new_name_no_quotes = new_name
         new_name = '"' + new_name + '"'  # put the new name into quotes to protect spaces
         self._hypervisor.send("atmsw rename {name} {new_name}".format(name=self._name,
                                                                       new_name=new_name))
@@ -102,7 +112,9 @@ class ATMSwitch(object):
                                                                              id=self._id,
                                                                              new_name=new_name))
 
+        self._allocated_names.remove(self.name)
         self._name = new_name
+        self._allocated_names.append(new_name_no_quotes)
 
     @property
     def hypervisor(self):
@@ -153,6 +165,7 @@ class ATMSwitch(object):
         log.info("ATM switch {name} [id={id}] has been deleted".format(name=self._name,
                                                                        id=self._id))
         self._hypervisor.devices.remove(self)
+        self._allocated_names.remove(self.name)
 
     def has_port(self, port):
         """
diff --git a/gns3server/modules/dynamips/nodes/bridge.py b/gns3server/modules/dynamips/nodes/bridge.py
index 4e86d161..ffa1e51d 100644
--- a/gns3server/modules/dynamips/nodes/bridge.py
+++ b/gns3server/modules/dynamips/nodes/bridge.py
@@ -31,6 +31,8 @@ class Bridge(object):
     :param name: name for this bridge
     """
 
+    _allocated_names = []
+
     def __init__(self, hypervisor, name):
 
         self._hypervisor = hypervisor
@@ -57,11 +59,14 @@ class Bridge(object):
         :param new_name: New name for this bridge
         """
 
+        new_name_no_quotes = new_name
         new_name = '"' + new_name + '"'  # put the new name into quotes to protect spaces
         self._hypervisor.send("nio_bridge rename {name} {new_name}".format(name=self._name,
                                                                            new_name=new_name))
 
+        self._allocated_names.remove(self.name)
         self._name = new_name
+        self._allocated_names.append(new_name_no_quotes)
 
     @property
     def hypervisor(self):
@@ -99,6 +104,7 @@ class Bridge(object):
 
         self._hypervisor.send("nio_bridge delete {}".format(self._name))
         self._hypervisor.devices.remove(self)
+        self._allocated_names.remove(self.name)
 
     def add_nio(self, nio):
         """
diff --git a/gns3server/modules/dynamips/nodes/c2600.py b/gns3server/modules/dynamips/nodes/c2600.py
index 35a6fc4c..a110a928 100644
--- a/gns3server/modules/dynamips/nodes/c2600.py
+++ b/gns3server/modules/dynamips/nodes/c2600.py
@@ -44,16 +44,16 @@ class C2600(Router):
 
     # adapters to insert by default corresponding the
     # chosen chassis.
-    integrated_adapters = {'2610': C2600_MB_1E,
-                           '2611': C2600_MB_2E,
-                           '2620': C2600_MB_1FE,
-                           '2621': C2600_MB_2FE,
-                           '2610XM': C2600_MB_1FE,
-                           '2611XM': C2600_MB_2FE,
-                           '2620XM': C2600_MB_1FE,
-                           '2621XM': C2600_MB_2FE,
-                           '2650XM': C2600_MB_1FE,
-                           '2651XM': C2600_MB_2FE}
+    integrated_adapters = {"2610": C2600_MB_1E,
+                           "2611": C2600_MB_2E,
+                           "2620": C2600_MB_1FE,
+                           "2621": C2600_MB_2FE,
+                           "2610XM": C2600_MB_1FE,
+                           "2611XM": C2600_MB_2FE,
+                           "2620XM": C2600_MB_1FE,
+                           "2621XM": C2600_MB_2FE,
+                           "2650XM": C2600_MB_1FE,
+                           "2651XM": C2600_MB_2FE}
 
     def __init__(self, hypervisor, name=None, chassis="2610"):
         Router.__init__(self, hypervisor, name, platform="c2600")
diff --git a/gns3server/modules/dynamips/nodes/ethernet_switch.py b/gns3server/modules/dynamips/nodes/ethernet_switch.py
index 2d0ad406..74d4d86c 100644
--- a/gns3server/modules/dynamips/nodes/ethernet_switch.py
+++ b/gns3server/modules/dynamips/nodes/ethernet_switch.py
@@ -36,6 +36,7 @@ class EthernetSwitch(object):
     :param name: name for this switch
     """
 
+    _allocated_names = []
     _instance_count = 1
 
     def __init__(self, hypervisor, name=None):
@@ -46,8 +47,15 @@ class EthernetSwitch(object):
 
         # let's create a unique name if none has been chosen
         if not name:
-            name = "SW" + str(self._id)
+            name_id = self._id
+            while True:
+                name = "SW" + str(name_id)
+                # check if the name has already been allocated to another switch
+                if name not in self._allocated_names:
+                    break
+                name_id += 1
 
+        self._allocated_names.append(name)
         self._hypervisor = hypervisor
         self._name = '"' + name + '"'  # put name into quotes to protect spaces
         self._hypervisor.send("ethsw create {}".format(self._name))
@@ -62,10 +70,11 @@ class EthernetSwitch(object):
     @classmethod
     def reset(cls):
         """
-        Reset the instance count.
+        Resets the instance count and the allocated names list.
         """
 
         cls._instance_count = 1
+        cls._allocated_names.clear()
 
     @property
     def id(self):
@@ -95,6 +104,7 @@ class EthernetSwitch(object):
         :param new_name: New name for this switch
         """
 
+        new_name_no_quotes = new_name
         new_name = '"' + new_name + '"'  # put the new name into quotes to protect spaces
         self._hypervisor.send("ethsw rename {name} {new_name}".format(name=self._name,
                                                                       new_name=new_name))
@@ -103,7 +113,9 @@ class EthernetSwitch(object):
                                                                                   id=self._id,
                                                                                   new_name=new_name))
 
+        self._allocated_names.remove(self.name)
         self._name = new_name
+        self._allocated_names.append(new_name_no_quotes)
 
     @property
     def hypervisor(self):
@@ -154,6 +166,7 @@ class EthernetSwitch(object):
         log.info("Ethernet switch {name} [id={id}] has been deleted".format(name=self._name,
                                                                             id=self._id))
         self._hypervisor.devices.remove(self)
+        self._allocated_names.remove(self.name)
 
     def add_nio(self, nio, port):
         """
diff --git a/gns3server/modules/dynamips/nodes/frame_relay_switch.py b/gns3server/modules/dynamips/nodes/frame_relay_switch.py
index 4b4cd64d..0776e61a 100644
--- a/gns3server/modules/dynamips/nodes/frame_relay_switch.py
+++ b/gns3server/modules/dynamips/nodes/frame_relay_switch.py
@@ -35,6 +35,7 @@ class FrameRelaySwitch(object):
     :param name: name for this switch
     """
 
+    _allocated_names = []
     _instance_count = 1
 
     def __init__(self, hypervisor, name=None):
@@ -45,8 +46,15 @@ class FrameRelaySwitch(object):
 
         # let's create a unique name if none has been chosen
         if not name:
-            name = "FR" + str(self._id)
+            name_id = self._id
+            while True:
+                name = "FR" + str(name_id)
+                # check if the name has already been allocated to another switch
+                if name not in self._allocated_names:
+                    break
+                name_id += 1
 
+        self._allocated_names.append(name)
         self._hypervisor = hypervisor
         self._name = '"' + name + '"'  # put name into quotes to protect spaces
         self._hypervisor.send("frsw create {}".format(self._name))
@@ -61,10 +69,11 @@ class FrameRelaySwitch(object):
     @classmethod
     def reset(cls):
         """
-        Reset the instance count.
+        Resets the instance count and the allocated names list.
         """
 
         cls._instance_count = 1
+        cls._allocated_names.clear()
 
     @property
     def id(self):
@@ -94,6 +103,7 @@ class FrameRelaySwitch(object):
         :param new_name: New name for this switch
         """
 
+        new_name_no_quotes = new_name
         new_name = '"' + new_name + '"'  # put the new name into quotes to protect spaces
         self._hypervisor.send("frsw rename {name} {new_name}".format(name=self._name,
                                                                      new_name=new_name))
@@ -102,7 +112,9 @@ class FrameRelaySwitch(object):
                                                                                      id=self._id,
                                                                                      new_name=new_name))
 
+        self._allocated_names.remove(self.name)
         self._name = new_name
+        self._allocated_names.append(new_name_no_quotes)
 
     @property
     def hypervisor(self):
@@ -153,6 +165,7 @@ class FrameRelaySwitch(object):
         log.info("Frame Relay switch {name} [id={id}] has been deleted".format(name=self._name,
                                                                                id=self._id))
         self._hypervisor.devices.remove(self)
+        self._allocated_names.remove(self.name)
 
     def has_port(self, port):
         """
diff --git a/gns3server/modules/dynamips/nodes/hub.py b/gns3server/modules/dynamips/nodes/hub.py
index b1e6d674..2cf943bd 100644
--- a/gns3server/modules/dynamips/nodes/hub.py
+++ b/gns3server/modules/dynamips/nodes/hub.py
@@ -45,8 +45,15 @@ class Hub(Bridge):
 
         # let's create a unique name if none has been chosen
         if not name:
-            name = "Hub" + str(self._id)
+            name_id = self._id
+            while True:
+                name = "Hub" + str(name_id)
+                # check if the name has already been allocated to another switch
+                if name not in self._allocated_names:
+                    break
+                name_id += 1
 
+        self._allocated_names.append(name)
         self._mapping = {}
         Bridge.__init__(self, hypervisor, name)
 
@@ -56,10 +63,11 @@ class Hub(Bridge):
     @classmethod
     def reset(cls):
         """
-        Reset the instance count.
+        Resets the instance count and the allocated names list.
         """
 
         cls._instance_count = 1
+        cls._allocated_names.clear()
 
     @property
     def id(self):
diff --git a/gns3server/modules/dynamips/nodes/router.py b/gns3server/modules/dynamips/nodes/router.py
index 95944ff7..88ab62f7 100644
--- a/gns3server/modules/dynamips/nodes/router.py
+++ b/gns3server/modules/dynamips/nodes/router.py
@@ -22,6 +22,7 @@ http://github.com/GNS3/dynamips/blob/master/README.hypervisor#L77
 
 from __future__ import unicode_literals
 from ..dynamips_error import DynamipsError
+import time
 import sys
 import os
 
@@ -39,6 +40,7 @@ class Router(object):
     :param ghost_flag: used when creating a ghost IOS.
     """
 
+    _allocated_names = []
     _instance_count = 1
     _status = {0: "inactive",
                1: "shutting down",
@@ -53,8 +55,15 @@ class Router(object):
 
         # let's create a unique name if none has been chosen
         if not name:
-            name = "R" + str(self._id)
+            name_id = self._id
+            while True:
+                name = "R" + str(name_id)
+                # check if the name has already been allocated to another router
+                if name not in self._allocated_names:
+                    break
+                name_id += 1
 
+        self._allocated_names.append(name)
         self._hypervisor = hypervisor
         self._name = '"' + name + '"'  # put name into quotes to protect spaces
         self._platform = platform
@@ -106,10 +115,11 @@ class Router(object):
     @classmethod
     def reset(cls):
         """
-        Reset the instance count.
+        Resets the instance count and the allocated names list.
         """
 
         cls._instance_count = 1
+        cls._allocated_names.clear()
 
     def defaults(self):
         """
@@ -179,6 +189,10 @@ class Router(object):
         :param new_name: new name string
         """
 
+        if new_name in self._allocated_names:
+            raise DynamipsError('Name "{}" is already used by another router'.format(new_name))
+
+        new_name_no_quotes = new_name
         new_name = '"' + new_name + '"'  # put the new name into quotes to protect spaces
         self._hypervisor.send("vm rename {name} {new_name}".format(name=self._name,
                                                                    new_name=new_name))
@@ -187,7 +201,9 @@ class Router(object):
                                                                          id=self._id,
                                                                          new_name=new_name))
 
+        self._allocated_names.remove(self.name)
         self._name = new_name
+        self._allocated_names.append(new_name_no_quotes)
 
     @property
     def platform(self):
@@ -237,6 +253,7 @@ class Router(object):
         self._hypervisor.devices.remove(self)
 
         log.info("router {name} [id={id}] has been deleted".format(name=self._name, id=self._id))
+        self._allocated_names.remove(self.name)
 
     def start(self):
         """
@@ -457,7 +474,7 @@ class Router(object):
                                                                                                old_ram=self._ram,
                                                                                                new_ram=ram))
 
-        self._hypervisor.decrease_memory_load(self._ram)
+        self._hypervisor.decrease_memory_load(ram)
         self._ram = ram
         self._hypervisor.increase_memory_load(self._ram)
 
@@ -627,7 +644,17 @@ class Router(object):
         :returns: list of idle PC proposal
         """
 
-        return self._hypervisor.send("vm get_idle_pc_prop {} 0".format(self._name))
+        if not self.is_running():
+            # router is not running
+            raise DynamipsError("router {name} is not running".format(name=self._name))
+
+        log.info("router {name} [id={id}] has started calculating idle-pc values".format(name=self._name, id=self._id))
+        begin = time.time()
+        idlepcs = self._hypervisor.send("vm get_idle_pc_prop {} 0".format(self._name))
+        log.info("router {name} [id={id}] has finished calculating idle-pc values after {time:.4f} seconds".format(name=self._name,
+                                                                                                                   id=self._id,
+                                                                                                                   time=time.time() - begin))
+        return idlepcs
 
     def show_idle_pc_prop(self):
         """
@@ -636,6 +663,10 @@ class Router(object):
         :returns: list of idle PC proposal
         """
 
+        if not self.is_running():
+            # router is not running
+            raise DynamipsError("router {name} is not running".format(name=self._name))
+
         return self._hypervisor.send("vm show_idle_pc_prop {} 0".format(self._name))
 
     @property
diff --git a/gns3server/server.py b/gns3server/server.py
index c90b085a..28e99882 100644
--- a/gns3server/server.py
+++ b/gns3server/server.py
@@ -96,7 +96,7 @@ class Server(object):
         tornado.autoreload.add_reload_hook(functools.partial(self._cleanup, stop=False))
 
         def signal_handler(signum=None, frame=None):
-            log.warning("Got signal {}, exiting...".format(signum))
+            log.warning("Server got signal {}, exiting...".format(signum))
             self._cleanup()
 
         for sig in [signal.SIGTERM, signal.SIGINT, signal.SIGHUP, signal.SIGQUIT]:
@@ -139,17 +139,19 @@ class Server(object):
 
     def _cleanup(self, stop=True):
         """
-        Shutdowns running module processes
+        Shutdowns any running module processes
         and close remaining Tornado ioloop file descriptors
 
-        :param stop: Stop the ioloop if True (default)
+        :param stop: stops the ioloop if True (default)
         """
 
         # terminate all modules
         for module in self._modules:
-            log.info("terminating {}".format(module.name))
-            module.terminate()
             module.join(timeout=1)
+            if module.is_alive():
+                log.info("terminating {}".format(module.name))
+                module.terminate()
+                module.join(timeout=1)
 
         ioloop = tornado.ioloop.IOLoop.instance()
         # close any fd that would have remained open...