From 9744849712531f0385ca5b99cc1b9294e6d14b54 Mon Sep 17 00:00:00 2001
From: Ivan Kolodyazhny <e0ne@e0ne.info>
Date: Thu, 17 Sep 2020 19:14:22 +0300
Subject: [PATCH] Rollback volume status if backup service is unavailable

We should not keep volume in 'backing-up' state if backup creation
process failed. It should be reverted to the previous state.

Change-Id: I33d4569df439fa59dec847f8dbc9f516a4839070
Closes-Bug: #1896087
---
 cinder/scheduler/manager.py                          |  6 +++++-
 cinder/tests/unit/scheduler/test_scheduler.py        | 12 ++++++++++--
 ...6087-rollback-volume-status-bd04951f929bb88d.yaml |  7 +++++++
 3 files changed, 22 insertions(+), 3 deletions(-)
 create mode 100644 releasenotes/notes/bug-1896087-rollback-volume-status-bd04951f929bb88d.yaml

diff --git a/cinder/scheduler/manager.py b/cinder/scheduler/manager.py
index 4a16696e86e..0832f387a51 100644
--- a/cinder/scheduler/manager.py
+++ b/cinder/scheduler/manager.py
@@ -629,13 +629,17 @@ class SchedulerManager(manager.CleanableManager, manager.Manager):
         return requested, not_requested
 
     def create_backup(self, context, backup):
-        volume = self.db.volume_get(context, backup.volume_id)
+        volume_id = backup.volume_id
+        volume = self.db.volume_get(context, volume_id)
         try:
             host = self.driver.get_backup_host(volume)
             backup.host = host
             backup.save()
             self.backup_api.create_backup(context, backup)
         except exception.ServiceNotFound:
+            self.db.volume_update(context, volume_id,
+                                  {'status': volume['previous_status'],
+                                   'previous_status': volume['status']})
             msg = "Service not found for creating backup."
             LOG.error(msg)
             vol_utils.update_backup_error(backup, msg)
diff --git a/cinder/tests/unit/scheduler/test_scheduler.py b/cinder/tests/unit/scheduler/test_scheduler.py
index 53b65662bc8..4036e7d59ab 100644
--- a/cinder/tests/unit/scheduler/test_scheduler.py
+++ b/cinder/tests/unit/scheduler/test_scheduler.py
@@ -605,9 +605,12 @@ class SchedulerManagerTestCase(test.TestCase):
     @mock.patch('cinder.volume.volume_utils.update_backup_error')
     @mock.patch('cinder.scheduler.driver.Scheduler.get_backup_host')
     @mock.patch('cinder.db.volume_get')
-    def test_create_backup_no_service(self, mock_volume_get, mock_host,
-                                      mock_error):
+    @mock.patch('cinder.db.volume_update')
+    def test_create_backup_no_service(self, mock_volume_update,
+                                      mock_volume_get, mock_host, mock_error):
         volume = fake_volume.fake_db_volume()
+        volume['status'] = 'backing-up'
+        volume['previous_status'] = 'available'
         mock_volume_get.return_value = volume
         mock_host.side_effect = exception.ServiceNotFound(
             service_id='cinder-volume')
@@ -617,6 +620,11 @@ class SchedulerManagerTestCase(test.TestCase):
 
         mock_host.assert_called_once_with(volume)
         mock_volume_get.assert_called_once_with(self.context, backup.volume_id)
+        mock_volume_update.assert_called_once_with(
+            self.context,
+            backup.volume_id,
+            {'status': 'available',
+             'previous_status': 'backing-up'})
         mock_error.assert_called_once_with(
             backup, 'Service not found for creating backup.')
 
diff --git a/releasenotes/notes/bug-1896087-rollback-volume-status-bd04951f929bb88d.yaml b/releasenotes/notes/bug-1896087-rollback-volume-status-bd04951f929bb88d.yaml
new file mode 100644
index 00000000000..41700caf2cd
--- /dev/null
+++ b/releasenotes/notes/bug-1896087-rollback-volume-status-bd04951f929bb88d.yaml
@@ -0,0 +1,7 @@
+---
+fixes:
+  - |
+    `Bug #1896087 <https://bugs.launchpad.net/cinder/+bug/1896087>`_:
+    Volume status will be rolled back to the previous state if backup creation
+    fails when backup service is not available
+