diff --git a/neutron/plugins/cisco/db/n1kv_db_v2.py b/neutron/plugins/cisco/db/n1kv_db_v2.py
index 4f47b1ced6..51b7c6a77c 100644
--- a/neutron/plugins/cisco/db/n1kv_db_v2.py
+++ b/neutron/plugins/cisco/db/n1kv_db_v2.py
@@ -269,7 +269,8 @@ def reserve_vlan(db_session, network_profile):
             physical_network = alloc.physical_network
             alloc.allocated = True
             return (physical_network, segment_type, segment_id, "0.0.0.0")
-        raise q_exc.NoNetworkAvailable()
+        raise c_exc.NoMoreNetworkSegments(
+            network_profile_name=network_profile.name)
 
 
 def reserve_vxlan(db_session, network_profile):
@@ -297,7 +298,8 @@ def reserve_vxlan(db_session, network_profile):
             alloc.allocated = True
             return (physical_network, segment_type,
                     segment_id, get_multicast_ip(network_profile))
-        raise q_exc.NoNetworkAvailable()
+        raise c_exc.NoMoreNetworkSegments(
+            network_profile_name=network_profile.name)
 
 
 def alloc_network(db_session, network_profile_id):
@@ -310,14 +312,10 @@ def alloc_network(db_session, network_profile_id):
     with db_session.begin(subtransactions=True):
         network_profile = get_network_profile(db_session,
                                               network_profile_id)
-        try:
-            if network_profile.segment_type == c_const.NETWORK_TYPE_VLAN:
-                return reserve_vlan(db_session, network_profile)
-            else:
-                return reserve_vxlan(db_session, network_profile)
-        except q_exc.NoNetworkAvailable:
-            raise c_exc.NoMoreNetworkSegments(
-                network_profile_name=network_profile.name)
+        if network_profile.segment_type == c_const.NETWORK_TYPE_VLAN:
+            return reserve_vlan(db_session, network_profile)
+        else:
+            return reserve_vxlan(db_session, network_profile)
 
 
 def reserve_specific_vlan(db_session, physical_network, vlan_id):
@@ -908,10 +906,7 @@ class NetworkProfile_db_mixin(object):
                         profile dictionary. Only these fields will be returned
         :returns: network profile dictionary
         """
-        try:
-            profile = get_network_profile(context.session, id)
-        except exc.NoResultFound:
-            raise c_exc.NetworkProfileIdNotFound(profile_id=id)
+        profile = get_network_profile(context.session, id)
         return self._make_network_profile_dict(profile, fields)
 
     def get_network_profiles(self, context, filters=None, fields=None):
@@ -1087,10 +1082,7 @@ class PolicyProfile_db_mixin(object):
                         profile dictionary. Only these fields will be returned
         :returns: policy profile dictionary
         """
-        try:
-            profile = get_policy_profile(context.session, id)
-        except exc.NoResultFound:
-            raise c_exc.PolicyProfileIdNotFound(profile_id=id)
+        profile = get_policy_profile(context.session, id)
         return self._make_policy_profile_dict(profile, fields)
 
     def get_policy_profiles(self, context, filters=None, fields=None):
diff --git a/neutron/plugins/cisco/network_plugin.py b/neutron/plugins/cisco/network_plugin.py
index bfd5ad9e0f..c0ef874eb4 100644
--- a/neutron/plugins/cisco/network_plugin.py
+++ b/neutron/plugins/cisco/network_plugin.py
@@ -281,12 +281,7 @@ class PluginV2(db_base_plugin_v2.NeutronDbPluginV2):
     def get_qos_details(self, tenant_id, qos_id):
         """Get QoS Details."""
         LOG.debug(_("get_qos_details() called"))
-        try:
-            qos_level = cdb.get_qos(tenant_id, qos_id)
-        except Exception:
-            raise cexc.QosNotFound(tenant_id=tenant_id,
-                                   qos_id=qos_id)
-        return qos_level
+        return cdb.get_qos(tenant_id, qos_id)
 
     def create_qos(self, tenant_id, qos_name, qos_desc):
         """Create a QoS level."""
@@ -297,23 +292,12 @@ class PluginV2(db_base_plugin_v2.NeutronDbPluginV2):
     def delete_qos(self, tenant_id, qos_id):
         """Delete a QoS level."""
         LOG.debug(_("delete_qos() called"))
-        try:
-            cdb.get_qos(tenant_id, qos_id)
-        except Exception:
-            raise cexc.QosNotFound(tenant_id=tenant_id,
-                                   qos_id=qos_id)
         return cdb.remove_qos(tenant_id, qos_id)
 
     def rename_qos(self, tenant_id, qos_id, new_name):
         """Rename QoS level."""
         LOG.debug(_("rename_qos() called"))
-        try:
-            cdb.get_qos(tenant_id, qos_id)
-        except Exception:
-            raise cexc.QosNotFound(tenant_id=tenant_id,
-                                   qos_id=qos_id)
-        qos = cdb.update_qos(tenant_id, qos_id, new_name)
-        return qos
+        return cdb.update_qos(tenant_id, qos_id, new_name)
 
     def get_all_credentials(self):
         """Get all credentials."""
diff --git a/neutron/plugins/cisco/nexus/cisco_nexus_network_driver_v2.py b/neutron/plugins/cisco/nexus/cisco_nexus_network_driver_v2.py
index bb0f8e6dec..dd09e92f94 100644
--- a/neutron/plugins/cisco/nexus/cisco_nexus_network_driver_v2.py
+++ b/neutron/plugins/cisco/nexus/cisco_nexus_network_driver_v2.py
@@ -71,7 +71,7 @@ class CiscoNEXUSDriver():
                     break
             else:
                 # Raise a Neutron exception. Include a description of
-                # the original ncclient exception.
+                # the original ncclient exception. No need to preserve T/B
                 raise cexc.NexusConfigFailed(config=config, exc=e)
 
     def get_credential(self, nexus_ip):
@@ -107,7 +107,7 @@ class CiscoNEXUSDriver():
             self.connections[nexus_host] = man
         except Exception as e:
             # Raise a Neutron exception. Include a description of
-            # the original ncclient exception.
+            # the original ncclient exception.  No need to preserve T/B.
             raise cexc.NexusConnectFailed(nexus_host=nexus_host, exc=e)
 
         return self.connections[nexus_host]