Raise an exception if starting neutron-l3-agent without creating a router

[Xiang Hui]

Version : Havana
OS : RHEL
Running Neutron services : neutron-server, neutron-openvswitch-agent, neutron-l3-agent
No routers being created, then the following exception will be raised.

2013-09-16 08:51:32.820 23737 ERROR neutron.openstack.common.rpc.amqp [-] Exception during message handling
2013-09-16 08:51:32.820 23737 TRACE neutron.openstack.common.rpc.amqp Traceback (most recent call last):
2013-09-16 08:51:32.820 23737 TRACE neutron.openstack.common.rpc.amqp File "/usr/lib/python2.6/site-packages/neutron/openstack/common/rpc/amqp.py", line 438, in _process_data
2013-09-16 08:51:32.820 23737 TRACE neutron.openstack.common.rpc.amqp **args)
2013-09-16 08:51:32.820 23737 TRACE neutron.openstack.common.rpc.amqp File "/usr/lib/python2.6/site-packages/neutron/common/rpc.py", line 44, in dispatch
2013-09-16 08:51:32.820 23737 TRACE neutron.openstack.common.rpc.amqp neutron_ctxt, version, method, namespace, **kwargs)
2013-09-16 08:51:32.820 23737 TRACE neutron.openstack.common.rpc.amqp File "/usr/lib/python2.6/site-packages/neutron/openstack/common/rpc/dispatcher.py", line 172, in dispatch
2013-09-16 08:51:32.820 23737 TRACE neutron.openstack.common.rpc.amqp result = getattr(proxyobj, method)(ctxt, **kwargs)
2013-09-16 08:51:32.820 23737 TRACE neutron.openstack.common.rpc.amqp File "/usr/lib/python2.6/site-packages/neutron/db/l3_rpc_base.py", line 54, in sync_routers
2013-09-16 08:51:32.820 23737 TRACE neutron.openstack.common.rpc.amqp l3plugin.auto_schedule_routers(context, host, router_ids)
2013-09-16 08:51:32.820 23737 TRACE neutron.openstack.common.rpc.amqp File "/usr/lib/python2.6/site-packages/neutron/db/l3_agentschedulers_db.py", line 241, in auto_schedule_routers
2013-09-16 08:51:32.820 23737 TRACE neutron.openstack.common.rpc.amqp self, context, host, router_ids)
2013-09-16 08:51:32.820 23737 TRACE neutron.openstack.common.rpc.amqp File "/usr/lib/python2.6/site-packages/neutron/scheduler/l3_agent_scheduler.py", line 113, in auto_schedule_routers
2013-09-16 08:51:32.820 23737 TRACE neutron.openstack.common.rpc.amqp context.session.add(binding)
2013-09-16 08:51:32.820 23737 TRACE neutron.openstack.common.rpc.amqp File "/usr/lib64/python2.6/site-packages/sqlalchemy/orm/session.py", line 449, in __exit__
2013-09-16 08:51:32.820 23737 TRACE neutron.openstack.common.rpc.amqp self.commit()
2013-09-16 08:51:32.820 23737 TRACE neutron.openstack.common.rpc.amqp File "/usr/lib64/python2.6/site-packages/sqlalchemy/orm/session.py", line 361, in commit
2013-09-16 08:51:32.820 23737 TRACE neutron.openstack.common.rpc.amqp self._prepare_impl()
2013-09-16 08:51:32.820 23737 TRACE neutron.openstack.common.rpc.amqp File "/usr/lib64/python2.6/site-packages/sqlalchemy/orm/session.py", line 340, in _prepare_impl
2013-09-16 08:51:32.820 23737 TRACE neutron.openstack.common.rpc.amqp self.session.flush()
2013-09-16 08:51:32.820 23737 TRACE neutron.openstack.common.rpc.amqp File "/usr/lib/python2.6/site-packages/neutron/openstack/common/db/sqlalchemy/session.py", line 542, in _wrap
2013-09-16 08:51:32.820 23737 TRACE neutron.openstack.common.rpc.amqp raise exception.DBError(e)
2013-09-16 08:51:32.820 23737 TRACE neutron.openstack.common.rpc.amqp DBError: (IntegrityError) (1452, 'Cannot add or update a child row: a foreign key constraint fails (`ovs_neutron`.`routerl3agentbindings`, CONSTRAINT `routerl3agentbindings_ibfk_1` FOREIGN KEY (`router_id`) REFERENCES `routers` (`id`) ON DELETE CASCADE)') 'INSERT INTO routerl3agentbindings (id, router_id, l3_agent_id) VALUES (%s, %s, %s)' ('28570d41-e7ab-4ca5-bed5-922bfbc154fc', '', '0214005e-8876-4bb1-a3b5-68f629b6e987')
2013-09-16 08:51:32.820 23737 TRACE neutron.openstack.common.rpc.amqp

The root cause is that the router_ids transferred is defined as [''], which is not None, but have an invalid empty value, the DB can't take this value in.

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/46863

[Salvatore Orlando (salvatore-orlando)]

This looks to me a duplicate of https://bugs.launchpad.net/neutron/+bug/1210877

In that case, thanks for fixing two bugs with one patch!

[Xiang Hui (xianghui)]

Thanks Salvatore, I have missed this bug before.

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/46863
Committed: http://github.com/openstack/neutron/commit/96e0eb23a458f068f540d98132ee261053c45585
Submitter: Jenkins
Branch: master

commit 96e0eb23a458f068f540d98132ee261053c45585
Author: Hui HX Xiang <email address hidden>
Date: Mon Sep 16 19:38:56 2013 -0700

    Raise an exception if no router_id provided

    IF both service neutron-l3-agent and neutron-server are up,
    but no router id configured in /etc/neutron/l3_agent.ini, an
    exception will be raised on DB as "DBError: IntegrityError",
    because the variable router_ids has a default '' value that
    doesn't match the DB grammar.

        * Check router id is specified in _init_() of l3 when
          not using namespace.
        * Move part of checking config params actions to new function
          _check_config_params()
        * Add corresponding unit tests.

    Closes-Bug: #1226366

    Change-Id: I905f8a4061c5b250782e025681dfefcc41c8c03c