diff --git a/plstackapi/core/api/subnets.py b/plstackapi/core/api/subnets.py
index 1da9cf1..f72595a 100644
--- a/plstackapi/core/api/subnets.py
+++ b/plstackapi/core/api/subnets.py
@@ -55,8 +55,7 @@
     driver = OpenStackDriver(client = auth_check(auth))   
     subnets = Subnet.objects.filter(**filter)
     for subnet in subnets:
-        try: driver.delete_router_interface(subnet.slice.router_id, subnet.subnet_id)
-        except: pass
+        driver.delete_router_interface(subnet.slice.router_id, subnet.subnet_id)
         driver.delete_subnet(subnet.subnet_id) 
         subnet.delete()
         del_route = 'route del -net %s' % subnet.cidr
diff --git a/plstackapi/core/models/sliver.py b/plstackapi/core/models/sliver.py
index 8f8dedc..82359ef 100644
--- a/plstackapi/core/models/sliver.py
+++ b/plstackapi/core/models/sliver.py
@@ -15,6 +15,7 @@
 class Sliver(PlCoreBase):
     instance_id = models.CharField(max_length=200, help_text="Nova instance id")    
     name = models.CharField(max_length=200, help_text="Sliver name")
+    ip = models.IPAddressField(help_text="Sliver ip address", blank=True, null=True)
     flavor = models.ForeignKey(Flavor, related_name='slivers')
     image = models.ForeignKey(Image, related_name='slivers')
     key = models.ForeignKey(Key, related_name='slivers')
diff --git a/plstackapi/core/models/subnet.py b/plstackapi/core/models/subnet.py
index 8b1969a..e94bfed 100644
--- a/plstackapi/core/models/subnet.py
+++ b/plstackapi/core/models/subnet.py
@@ -29,8 +29,7 @@
                                           end = self.end)
             self.subnet_id = quantum_subnet['id']
             # add subnet as interface to slice's router
-            try: driver.add_router_interface(self.slice.router_id, self.subnet_id)
-            except: pass
+            driver.add_router_interface(self.slice.router_id, self.subnet_id)
             add_route = 'route add -net %s dev br-ex gw 10.100.0.5' % self.cidr
             commands.getstatusoutput(add_route)
 
@@ -39,8 +38,7 @@
     def delete(self, *args, **kwds):
         driver = OpenStackDriver()
         if self.subnet_id:
-            try: driver.delete_router_interface(self.slice.router_id, self.subnet_id) 
-            except: pass
+            driver.delete_router_interface(self.slice.router_id, self.subnet_id) 
             driver.delete_subnet(self.subnet_id)
             del_route = 'route del -net %s' % self.cidr 
         commands.getstatusoutput(del_route)