Merge "Added support for live migration on non-shared storage"

watcher/applier/actions/migration.py

@@ -21,7 +21,7 @@ from oslo_log import log
 import six
 import voluptuous
 
-from watcher._i18n import _
+from watcher._i18n import _, _LC
 from watcher.applier.actions import base
 from watcher.common import exception
 from watcher.common import nova_helper
@@ -76,6 +76,31 @@ class Migrate(base.BaseAction):
     def src_hypervisor(self):
         return self.input_parameters.get(self.SRC_HYPERVISOR)
 
+    def _live_migrate_instance(self, nova, destination):
+        result = None
+        try:
+            result = nova.live_migrate_instance(instance_id=self.instance_uuid,
+                                                dest_hostname=destination)
+        except nova_helper.nvexceptions.ClientException as e:
+            if e.code == 400:
+                LOG.debug("Live migration of instance %s failed. "
+                          "Trying to live migrate using block migration."
+                          % self.instance_uuid)
+                result = nova.live_migrate_instance(
+                    instance_id=self.instance_uuid,
+                    dest_hostname=destination,
+                    block_migration=True)
+            else:
+                LOG.debug("Nova client exception occured while live migrating "
+                          "instance %s.Exception: %s" %
+                          (self.instance_uuid, e))
+        except Exception:
+            LOG.critical(_LC("Unexpected error occured. Migration failed for"
+                             "instance %s. Leaving instance on previous "
+                             "host."), self.instance_uuid)
+
+        return result
+
     def migrate(self, destination):
         nova = nova_helper.NovaHelper(osc=self.osc)
         LOG.debug("Migrate instance %s to %s", self.instance_uuid,
@@ -83,8 +108,7 @@ class Migrate(base.BaseAction):
         instance = nova.find_instance(self.instance_uuid)
         if instance:
             if self.migration_type == 'live':
-                return nova.live_migrate_instance(
+                return self._live_migrate_instance(nova, destination)
-                    instance_id=self.instance_uuid, dest_hostname=destination)
             else:
                 raise exception.Invalid(
                     message=(_('Migration of type %(migration_type)s is not '

watcher/tests/applier/actions/test_migration.py

@@ -157,7 +157,10 @@ class TestMigration(base.TestCase):
     def test_execute_live_migration(self):
         self.m_helper.find_instance.return_value = self.INSTANCE_UUID
 
-        self.action.execute()
+        try:
+            self.action.execute()
+        except Exception as exc:
+            self.fail(exc)
 
         self.m_helper.live_migrate_instance.assert_called_once_with(
             instance_id=self.INSTANCE_UUID,
@@ -173,3 +176,31 @@ class TestMigration(base.TestCase):
             instance_id=self.INSTANCE_UUID,
             dest_hostname="hypervisor1-hostname"
         )
+
+    def test_live_migrate_non_shared_storage_instance(self):
+        self.m_helper.find_instance.return_value = self.INSTANCE_UUID
+
+        self.m_helper.live_migrate_instance.side_effect = [
+            nova_helper.nvexceptions.ClientException(400, "BadRequest"), True]
+
+        try:
+            self.action.execute()
+        except Exception as exc:
+            self.fail(exc)
+
+        self.m_helper.live_migrate_instance.assert_has_calls([
+            mock.call(instance_id=self.INSTANCE_UUID,
+                      dest_hostname="hypervisor2-hostname"),
+            mock.call(instance_id=self.INSTANCE_UUID,
+                      dest_hostname="hypervisor2-hostname",
+                      block_migration=True)
+            ])
+
+        expected = [mock.call.first(instance_id=self.INSTANCE_UUID,
+                                    dest_hostname="hypervisor2-hostname"),
+                    mock.call.second(instance_id=self.INSTANCE_UUID,
+                                     dest_hostname="hypervisor2-hostname",
+                                     block_migration=True)
+                    ]
+        self.m_helper.live_migrate_instance.mock_calls == expected
+        self.assertEqual(2, self.m_helper.live_migrate_instance.call_count)