This patch fixes the upstream bug 1431105 that is only fixed in Kilo.

commit 05f234481474aa05f59c4af459b4343d21397afc

Author: Kevin Benton <email address hidden>

Date: Wed Mar 11 18:32:52 2015 -0700

    Schedule net to a DHCP agt on subnet create

    Change the DHCP notifier behavior to schedule a network

    to a DHCP agent when a subnet is created rather than

    waiting for the first port to be created.

    This will reduce the possibility to get a VM port created

    and have it send a DHCP request before the DHCP agent is

    ready. Before, the network would be scheduled to an agent

    as a result of the API call to create the VM port, so the

    DHCP port wouldn't be created until after the VM port.

    After this patch, the network will have been scheduled to

    a DHCP agent before the first VM port is created.

    There is still a possibility that the DHCP agent could be

    responding so slowly that it doesn't create its port and

    activate the dnsmasq instance before the VM sends traffic.

    A proper fix will ensure that the dnsmasq instance is

    truly ready to serve requests for a new port will require

    significantly more code for barriers (either on the subnet

    creation, port creation, or the nova boot process) are too

    complex to add this late in the cycle.

    This patch also eliminates the logic in the n1kv plugin that

    was already doing the same thing.

    Closes-Bug: #1431105

    Change-Id: I1c1caed0fdda6b801375a07f9252a9127058a07e

--- neutron-2014.2.2/neutron/api/rpc/agentnotifiers/dhcp_rpc_agent_api.py	2015-02-05 07:45:33.000000000 -0800

+++ new/neutron/api/rpc/agentnotifiers/dhcp_rpc_agent_api.py	2015-10-13 15:48:35.280824405 -0700

@@ -63,8 +63,8 @@

                     {'network': {'id': network['id']}}, agent['host'])

         elif not existing_agents:

             LOG.warn(_('Unable to schedule network %s: no agents available; '

-                       'will retry on subsequent port creation events.'),

-                     network['id'])

+                       'will retry on subsequent port and subnet creation '

+                       'events.'), network['id'])

         return new_agents + existing_agents

     def _get_enabled_agents(self, context, network, agents, method, payload):

@@ -119,6 +119,7 @@

             # schedule the network first, if needed

             schedule_required = (

+                method == 'subnet_create_end' or

                 method == 'port_create_end' and

                 not self._is_reserved_dhcp_port(payload['port']))

             if schedule_required:

--- neutron-2014.2.2/neutron/plugins/cisco/n1kv/n1kv_neutron_plugin.py	2015-02-05 07:45:33.000000000 -0800

+++ new/neutron/plugins/cisco/n1kv/n1kv_neutron_plugin.py	2015-10-16 13:04:56.539001054 -0700

@@ -1293,10 +1293,6 @@

                       self).delete_subnet(context, sub['id'])

         else:

             LOG.debug(_("Created subnet: %s"), sub['id'])

-            if not q_conf.CONF.network_auto_schedule:

-                # Schedule network to a DHCP agent

-                net = self.get_network(context, sub['network_id'])

-                self.schedule_network(context, net)

             return sub

     def update_subnet(self, context, id, subnet):