Not remove the running router when MQ is unreachable

When the L3 agent get a router update notification, it will try to
retrieve the router info from neutron server. But at this time, if
the message queue is down/unreachable. It will get exceptions related
message queue. The resync actions will be run then. Sometimes, rabbitMQ
cluster is not so much easy to recover. Then Long time MQ recover time
will cause the router info sync RPC never get successful until it meets
the max retry time. Then the bad thing happens, L3 agent is trying to
remove the router now. It basically shutdown all the existing L3 traffic
of this router.

This patch directly removes the final router removal action, let the
router run as it is.

Conflicts:
        neutron/agent/l3/agent.py
        neutron/tests/unit/agent/l3/test_agent.py

Closes-Bug: #1871850
Change-Id: I9062638366b45a7a930f31185cd6e23901a43957
(cherry picked from commit 12b9149e20)
This commit is contained in:
LIU Yulong 2020-04-11 08:41:28 +08:00
parent 6a10523df6
commit ec6c98060d
2 changed files with 33 additions and 12 deletions

View File

@ -567,9 +567,6 @@ class L3NATAgent(ha.AgentMixin,
if router_update.hit_retry_limit():
LOG.warning("Hit retry limit with router update for %s, action %s",
router_update.id, router_update.action)
if router_update.action != queue.DELETE_ROUTER:
LOG.debug("Deleting router %s", router_update.id)
self._safe_router_removed(router_update.id)
return
router_update.timestamp = timeutils.utcnow()
router_update.priority = priority

View File

@ -2694,35 +2694,59 @@ class TestBasicRouterOperations(BasicRouterOperationsFramework):
self._test_process_routers_update_rpc_timeout(ext_net_call=True,
ext_net_call_failed=True)
@mock.patch.object(pd, 'remove_router')
def _test_process_routers_update_router_deleted(self, remove_router,
error=False):
def test_process_routers_update_router_update(self):
agent = l3_agent.L3NATAgent(HOSTNAME, self.conf)
agent._queue = mock.Mock()
update = mock.Mock()
update.resource = None
update.action = 1 # ROUTER_DELETED
update.action = resource_processing_queue.ADD_UPDATE_ROUTER
router_info = mock.MagicMock()
agent.router_info[update.id] = router_info
router_processor = mock.Mock()
agent._queue.each_update_to_next_resource.side_effect = [
[(router_processor, update)]]
agent._resync_router = mock.Mock()
agent._safe_router_removed = mock.Mock()
agent.plugin_rpc = mock.MagicMock()
agent.plugin_rpc.get_routers.side_effect = (
Exception("Failed to get router info"))
# start test
agent._process_router_update()
router_info.delete.assert_not_called()
self.assertFalse(router_info.delete.called)
self.assertTrue(agent.router_info)
self.assertTrue(agent._resync_router.called)
self.assertFalse(agent._safe_router_removed.called)
def _test_process_routers_update_router_deleted(self,
error=False):
agent = l3_agent.L3NATAgent(HOSTNAME, self.conf)
agent._queue = mock.Mock()
update = mock.Mock()
update.resource = None
update.action = resource_processing_queue.DELETE_ROUTER
router_info = mock.MagicMock()
agent.router_info[update.id] = router_info
router_processor = mock.Mock()
agent._queue.each_update_to_next_resource.side_effect = [
[(router_processor, update)]]
agent._resync_router = mock.Mock()
agent._safe_router_removed = mock.Mock()
if error:
agent._safe_router_removed = mock.Mock()
agent._safe_router_removed.return_value = False
agent._process_router_update()
if error:
self.assertFalse(router_processor.fetched_and_processed.called)
agent._resync_router.assert_called_with(update)
self.assertFalse(remove_router.called)
self.assertTrue(agent._safe_router_removed.called)
else:
router_info.delete.assert_called_once_with()
self.assertFalse(agent.router_info)
router_info.delete.assert_not_called()
self.assertFalse(router_info.delete.called)
self.assertTrue(agent.router_info)
self.assertFalse(agent._resync_router.called)
router_processor.fetched_and_processed.assert_called_once_with(
update.timestamp)
self.assertTrue(remove_router.called)
self.assertTrue(agent._safe_router_removed.called)
def test_process_routers_update_router_deleted_success(self):
self._test_process_routers_update_router_deleted()