sync external routes
diff --git a/planetstack/openstack/driver.py b/planetstack/openstack/driver.py
index b9faa97..14eea41 100644
--- a/planetstack/openstack/driver.py
+++ b/planetstack/openstack/driver.py
@@ -239,7 +239,15 @@
                 self.delete_external_route(subnet)
         return 1
 
-    def add_external_route(self, subnet):
+    def get_external_routes(self):
+        status, output = commands.getstatusoutput('route')
+        routes = output.split('\n')[3:]
+        return routes
+
+    def add_external_route(self, subnet, routes=[]):
+        if not routes:
+            routes = self.get_external_routes()
+ 
         ports = self.shell.quantum.list_ports()['ports']
 
         gw_ip = subnet['gateway_ip']
@@ -262,8 +270,15 @@
                             ip_address = port['fixed_ips'][0]['ip_address']
 
         if ip_address:
-            cmd = "route add -net %s dev br-ex gw %s" % (subnet['cidr'], ip_address)
-            commands.getstatusoutput(cmd)
+            # check if external route already exists
+            route_exists = False
+            if routes:
+                for route in routes:
+                    if subnet['cidr'] in route and ip_address in route:
+                        route_exists = True
+            if not route_exists:
+                cmd = "route add -net %s dev br-ex gw %s" % (subnet['cidr'], ip_address)
+                commands.getstatusoutput(cmd)
 
         return 1
 
diff --git a/planetstack/openstack/observer.py b/planetstack/openstack/observer.py
index 6fcb3b4..8da0999 100644
--- a/planetstack/openstack/observer.py
+++ b/planetstack/openstack/observer.py
@@ -1,5 +1,6 @@
 import time
 import traceback
+import commands
 from datetime import datetime
 from collections import defaultdict
 from core.models import *
@@ -263,7 +264,7 @@
         for sliver in slivers:
             # update connection
             self.manager.init_admin(tenant=sliver.slice.name)
-            servers = self.manager.client.nova.servers.findall(id=sliver.instance_id)
+            servers = self.manager.driver.shell.nova.servers.findall(id=sliver.instance_id)
             if not servers:
                 continue
             server = servers[0]
@@ -273,3 +274,10 @@
             sliver.ip = ips[0]['addr']
             sliver.save()
             logger.info("saved sliver ip: %s %s" % (sliver, ips[0]))
+
+    def sync_external_routes(self):
+        routes = self.manager.driver.get_external_routes() 
+        subnets = self.manager.driver.shell.quantum.list_subnets()
+        for subnet in subnets:
+            self.manager.driver.add_external_route(subnet, routes)         
+