openstack/cinder
Code Issues Proposed changes

Add SIGHUP handlers to reset RPC version pins

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Adding SIGHUP handlers (by implementing reset from oslo.service) to
cinder-scheduler, cinder-backup and cinder-volume that reset cached RPC
version pins. This is to avoid the need to restart all the services when
upgrade of the deployment is completed.

Some changes go a little deep into the stack, because to reload all the
pins we need to recreate <service>.rpcapi.<service>API objects that are
stored in the memory.

Please note that SIGHUP signal is handled by oslo.service only when
service runs in daemon mode (without tty attached). To test this commit
in DevStack you need to add "&" to the end of the command that starts
the service.

Situation is more complicated with the API service, so we're leaving it
with restart required for now. In the deployments with HA cinder-api is
typically behind a load balancer, so restarting individual nodes
one-by-one should be easy.

DocImpact: Add information on rolling upgrades procedures to the docs.
Implements: blueprint rpc-object-compatibility

Change-Id: I03ed74e17dc9a4b9aa2ddcfbeb36a106a0f035f8
This commit is contained in:
Michał Dulko
2016-02-05 15:41:01 +01:00
parent 3631fd2576
commit c9a55d852e
10 changed files with 115 additions and 0 deletions
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15
cinder/tests/unit/scheduler/test_scheduler.py
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@@ -69,6 +69,21 @@ class SchedulerManagerTestCase(test.TestCase):
sleep_mock.assert_called_once_with(CONF.periodic_interval)
self.assertFalse(self.manager._startup_delay)
@mock.patch('cinder.rpc.LAST_RPC_VERSIONS', {'cinder-volume': '1.3'})
@mock.patch('cinder.rpc.LAST_OBJ_VERSIONS', {'cinder-volume': '1.5'})
def test_reset(self):
mgr = self.manager_cls()
volume_rpcapi = mgr.driver.volume_rpcapi
self.assertEqual('1.3', volume_rpcapi.client.version_cap)
self.assertEqual('1.5',
volume_rpcapi.client.serializer._base.version_cap)
mgr.reset()
volume_rpcapi = mgr.driver.volume_rpcapi
self.assertIsNone(volume_rpcapi.client.version_cap)
self.assertIsNone(volume_rpcapi.client.serializer._base.version_cap)
@mock.patch('cinder.scheduler.driver.Scheduler.'
'update_service_capabilities')
def test_update_service_capabilities_empty_dict(self, _mock_update_cap):