diff --git a/oml/localnodes.py b/oml/localnodes.py
index c601a23..1bcff99 100644
--- a/oml/localnodes.py
+++ b/oml/localnodes.py
@@ -3,7 +3,6 @@
 from __future__ import division
 
 import json
-import logging
 import socket
 import struct
 import thread
@@ -16,6 +15,7 @@ import state
 import db
 import user.models
 
+import logging
 logger = logging.getLogger('oml.localnodes')
 
 def can_connect(data):
@@ -49,14 +49,18 @@ class LocalNodesBase(Thread):
         self.start()
 
     def get_packet(self):
-        message = json.dumps({
-            'username': preferences.get('username', 'anonymous'),
-            'host': self.host,
-            'port': server['node_port'],
-            'cert': server['cert']
-        })
-        sig = sk.sign(message, encoding='base64')
-        packet = json.dumps([sig, USER_ID, message])
+        self.host = self.get_ip()
+        if self.host:
+            message = json.dumps({
+                'username': preferences.get('username', 'anonymous'),
+                'host': self.host,
+                'port': server['node_port'],
+                'cert': server['cert']
+            })
+            sig = sk.sign(message, encoding='base64')
+            packet = json.dumps([sig, USER_ID, message])
+        else:
+            packet = None
         return packet
 
     def get_socket(self):
@@ -66,9 +70,11 @@ class LocalNodesBase(Thread):
         pass
 
     def receive(self):
+        last = time.mktime(time.localtime())
         while self._active:
             try:
                 s = self.get_socket()
+                s.settimeout(2)
                 s.bind(('', self._PORT))
                 while self._active:
                     data, addr = s.recvfrom(1024)
@@ -78,11 +84,15 @@ class LocalNodesBase(Thread):
                         data = self.verify(data)
                         if data:
                             self.update_node(data)
+            except socket.timeout:
+                now = time.mktime(time.localtime())
+                if now - last > 60:
+                    last = now
+                    thread.start_new_thread(self.send, ())
             except:
                 logger.debug('receive failed. restart later', exc_info=1)
                 time.sleep(10)
 
-
     def verify(self, data):
         try:
             packet = json.loads(data)
@@ -129,7 +139,6 @@ class LocalNodesBase(Thread):
         pass
 
     def run(self):
-        self.host = self.get_ip()
         self.send()
         self.receive()
 
@@ -150,14 +159,15 @@ class LocalNodes4(LocalNodesBase):
 
     def send(self):
         packet = self.get_packet()
-        sockaddr = (self._BROADCAST, self._PORT)
-        s = socket.socket (socket.AF_INET, socket.SOCK_DGRAM)
-        s.setsockopt (socket.IPPROTO_IP, socket.IP_MULTICAST_TTL, self._TTL)
-        try:
-            s.sendto(packet + '\0', sockaddr)
-        except:
-            logger.debug('LocalNodes4.send failed', exc_info=1)
-        s.close()
+        if packet:
+            sockaddr = (self._BROADCAST, self._PORT)
+            s = socket.socket (socket.AF_INET, socket.SOCK_DGRAM)
+            s.setsockopt (socket.IPPROTO_IP, socket.IP_MULTICAST_TTL, self._TTL)
+            try:
+                s.sendto(packet + '\0', sockaddr)
+            except:
+                logger.debug('LocalNodes4.send failed', exc_info=1)
+            s.close()
 
     def get_socket(self):
         s = socket.socket (socket.AF_INET, socket.SOCK_DGRAM)
@@ -175,20 +185,21 @@ class LocalNodes6(LocalNodesBase):
     _BROADCAST = "ff02::1"
 
     def send(self):
-        logger.debug('send6')
         packet = self.get_packet()
-        ttl = struct.pack('@i', self._TTL)
-        address = self._BROADCAST + get_interface()
-        addrs = socket.getaddrinfo(address, self._PORT, socket.AF_INET6, socket.SOCK_DGRAM)
-        addr = addrs[0]
-        (family, socktype, proto, canonname, sockaddr) = addr
-        s = socket.socket(family, socktype, proto)
-        s.setsockopt(socket.IPPROTO_IPV6, socket.IPV6_MULTICAST_HOPS, ttl)
-        try:
-            s.sendto(packet + '\0', sockaddr)
-        except:
-            logger.debug('LocalNodes6.send failed', exc_info=1)
-        s.close()
+        if packet:
+            logger.debug('send6 %s', packet)
+            ttl = struct.pack('@i', self._TTL)
+            address = self._BROADCAST + get_interface()
+            addrs = socket.getaddrinfo(address, self._PORT, socket.AF_INET6, socket.SOCK_DGRAM)
+            addr = addrs[0]
+            (family, socktype, proto, canonname, sockaddr) = addr
+            s = socket.socket(family, socktype, proto)
+            s.setsockopt(socket.IPPROTO_IPV6, socket.IPV6_MULTICAST_HOPS, ttl)
+            try:
+                s.sendto(packet + '\0', sockaddr)
+            except:
+                logger.debug('LocalNodes6.send failed', exc_info=1)
+            s.close()
 
     def get_socket(self):
         s = socket.socket(socket.AF_INET6, socket.SOCK_DGRAM)
@@ -203,6 +214,7 @@ class LocalNodes6(LocalNodesBase):
 
 class LocalNodes(object):
 
+    _active = True
     _nodes4 = None
     _nodes6 = None
 
@@ -213,12 +225,21 @@ class LocalNodes(object):
         self._nodes4 = LocalNodes4(self._nodes)
         self._nodes6 = LocalNodes6(self._nodes)
 
+    def cleanup(self):
+        if self._active:
+            for id in self._nodes.keys():
+                if not can_connect(self._nodes[id]):
+                    del self._nodes[id]
+                if not self._active:
+                    break
+
     def get(self, user_id):
         if user_id in self._nodes:
             if can_connect(self._nodes[user_id]):
                 return self._nodes[user_id]
 
     def join(self):
+        self._active = False
         if self._nodes4:
             self._nodes4.join()
         if self._nodes6:
diff --git a/oml/nodes.py b/oml/nodes.py
index c0364a1..7399caf 100644
--- a/oml/nodes.py
+++ b/oml/nodes.py
@@ -358,10 +358,16 @@ class Nodes(Thread):
         self._q = Queue()
         self._running = True
         self._local = LocalNodes()
+        self._cleanup = PeriodicCallback(lambda: self.queue('cleanup'), 120000)
+        self._cleanup.start()
         Thread.__init__(self)
         self.daemon = True
         self.start()
 
+    def cleanup(self):
+        if self._running:
+            self._local.cleanup()
+
     def queue(self, *args):
         self._q.put(list(args))
 
@@ -396,7 +402,9 @@ class Nodes(Thread):
         while self._running:
             args = self._q.get()
             if args:
-                if args[0] == 'add':
+                if args[0] == 'cleanup':
+                    self.cleanup()
+                elif args[0] == 'add':
                     self._add(args[1])
                 else:
                     self._call(*args)