Added update-host for CGs in cinder-manage

Currently in cinder-manage, "update_host" command for consistency
groups is missing.

Hence, in a similar way like volumes and backups, 'update_host'
is added for Consistency Groups as well, because if host
configuration is changed then even if we change volumes and
backups using cinder-manage, we would have to go to the DB to
change our CGs.

Change-Id: I820ae9d17460a5aa7b3b2e41afc861e8bc0265a3
Closes-Bug: 1591153

cinder/cmd/manage.py

@@ -597,10 +597,33 @@ class ClusterCommands(BaseCommand):
             return 2
 
 
+class ConsistencyGroupCommands(object):
+    """Methods for managing consistency groups."""
+
+    @args('--currenthost', required=True, help='Existing CG host name')
+    @args('--newhost', required=True, help='New CG host name')
+    def update_cg_host(self, currenthost, newhost):
+        """Modify the host name associated with a Consistency Group.
+
+        Particularly to recover from cases where one has moved
+        a host from single backend to multi-backend, or changed the host
+        configuration option, or modified the backend_name in a multi-backend
+        config.
+        """
+
+        ctxt = context.get_admin_context()
+        groups = objects.ConsistencyGroupList.get_all(
+            ctxt, {'host': currenthost})
+        for gr in groups:
+            gr.host = newhost
+            gr.save()
+
+
 CATEGORIES = {
     'backup': BackupCommands,
     'config': ConfigCommands,
     'cluster': ClusterCommands,
+    'cg': ConsistencyGroupCommands,
     'db': DbCommands,
     'host': HostCommands,
     'logs': GetLogCommands,

cinder/tests/unit/test_cmd.py

@@ -751,6 +751,31 @@ class TestCinderManageCmd(test.TestCase):
         backup_update.assert_called_once_with(ctxt, fake.BACKUP_ID,
                                               {'host': 'fake_host2'})
 
+    @mock.patch('cinder.db.consistencygroup_update')
+    @mock.patch('cinder.db.consistencygroup_get_all')
+    @mock.patch('cinder.context.get_admin_context')
+    def test_update_consisgroup_host(self, get_admin_context,
+                                     consisgroup_get_all,
+                                     consisgroup_update):
+        ctxt = context.RequestContext(fake.USER_ID, fake.PROJECT_ID)
+        get_admin_context.return_value = ctxt
+        consisgroup = {'id': fake.CONSISTENCY_GROUP_ID,
+                       'user_id': fake.USER_ID,
+                       'project_id': fake.PROJECT_ID,
+                       'host': 'fake-host',
+                       'status': fields.ConsistencyGroupStatus.AVAILABLE
+                       }
+        consisgroup_get_all.return_value = [consisgroup]
+        consisgrup_cmds = cinder_manage.ConsistencyGroupCommands()
+        consisgrup_cmds.update_cg_host('fake_host', 'fake_host2')
+
+        get_admin_context.assert_called_once_with()
+        consisgroup_get_all.assert_called_once_with(
+            ctxt, filters={'host': 'fake_host'}, limit=None, marker=None,
+            offset=None, sort_dirs=None, sort_keys=None)
+        consisgroup_update.assert_called_once_with(
+            ctxt, fake.CONSISTENCY_GROUP_ID, {'host': 'fake_host2'})
+
     @mock.patch('cinder.utils.service_is_up')
     @mock.patch('cinder.db.service_get_all')
     @mock.patch('cinder.context.get_admin_context')

releasenotes/notes/consistency_group_manage-d30a2ad8917a7a86.yaml

@@ -0,0 +1,3 @@
+---
+features:
+  - Added update-host command for consistency groups in cinder-manage.