openstack/cinder
Code Issues Proposed changes

Backup snapshots

Browse Source 
Today we can backup a volume, but not a snapshot.
This patch adds support to backup snapshots and
provide another layer of data protection for the
user.

DocImpact
implements blueprint backup-snapshots

Change-Id: Ib4ab9ca9dc72b30151154f3f96037f9ce3c9c540
This commit is contained in:
Xing Yang 2015-10-09 21:57:18 -04:00
parent d7f1cde362
commit dbc345729e
17 changed files with 301 additions and 61 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

4
cinder/api/contrib/backups.py
View File

@ -263,6 +263,7 @@ class BackupsController(wsgi.Controller):
description = backup.get('description', None)
incremental = backup.get('incremental', False)
force = backup.get('force', False)
snapshot_id = backup.get('snapshot_id', None)
LOG.info(_LI("Creating backup of volume %(volume_id)s in container"
" %(container)s"),
{'volume_id': volume_id, 'container': container},
@ -271,7 +272,8 @@ class BackupsController(wsgi.Controller):
try:
new_backup = self.backup_api.create(context, name, description,
volume_id, container,
incremental, None, force)
incremental, None, force,
snapshot_id)
except exception.InvalidVolume as error:
raise exc.HTTPBadRequest(explanation=error.msg)
except exception.VolumeNotFound as error:

2
cinder/api/views/backups.py
View File

@ -78,6 +78,8 @@ class ViewBuilder(common.ViewBuilder):
'links': self._get_links(request, backup['id']),
'is_incremental': backup.is_incremental,
'has_dependent_backups': backup.has_dependent_backups,
'snapshot_id': backup.snapshot_id,
'data_timestamp': backup.data_timestamp,
}
}

54
cinder/backup/api.py
View File

@ -19,11 +19,14 @@
Handles all requests relating to the volume backups service.
"""
from datetime import datetime
from eventlet import greenthread
from oslo_config import cfg
from oslo_log import log as logging
from oslo_utils import excutils
from oslo_utils import strutils
from pytz import timezone
from cinder.backup import rpcapi as backup_rpcapi
from cinder import context
@ -150,20 +153,28 @@ class API(base.Base):
def create(self, context, name, description, volume_id,
container, incremental=False, availability_zone=None,
force=False):
force=False, snapshot_id=None):
"""Make the RPC call to create a volume backup."""
check_policy(context, 'create')
volume = self.volume_api.get(context, volume_id)
snapshot = None
if snapshot_id:
snapshot = self.volume_api.get_snapshot(context, snapshot_id)
if volume['status'] not in ["available", "in-use"]:
msg = (_('Volume to be backed up must be available '
'or in-use, but the current status is "%s".')
% volume['status'])
raise exception.InvalidVolume(reason=msg)
elif volume['status'] in ["in-use"] and not force:
elif volume['status'] in ["in-use"] and not snapshot_id and not force:
msg = _('Backing up an in-use volume must use '
'the force flag.')
raise exception.InvalidVolume(reason=msg)
elif snapshot_id and snapshot['status'] not in ["available"]:
msg = (_('Snapshot to be backed up must be available, '
'but the current status is "%s".')
% snapshot['status'])
raise exception.InvalidSnapshot(reason=msg)
previous_status = volume['status']
volume_host = volume_utils.extract_host(volume['host'], 'host')
@ -208,15 +219,36 @@ class API(base.Base):
raise exception.BackupLimitExceeded(
allowed=quotas[over])
# Find the latest backup of the volume and use it as the parent
# backup to do an incremental backup.
# Find the latest backup and use it as the parent backup to do an
# incremental backup.
latest_backup = None
if incremental:
backups = objects.BackupList.get_all_by_volume(context.elevated(),
volume_id)
if backups.objects:
latest_backup = max(backups.objects,
key=lambda x: x['created_at'])
# NOTE(xyang): The 'data_timestamp' field records the time
# when the data on the volume was first saved. If it is
# a backup from volume, 'data_timestamp' will be the same
# as 'created_at' for a backup. If it is a backup from a
# snapshot, 'data_timestamp' will be the same as
# 'created_at' for a snapshot.
# If not backing up from snapshot, the backup with the latest
# 'data_timestamp' will be the parent; If backing up from
# snapshot, the backup with the latest 'data_timestamp' will
# be chosen only if 'data_timestamp' is earlier than the
# 'created_at' timestamp of the snapshot; Otherwise, the
# backup will not be chosen as the parent.
# For example, a volume has a backup taken at 8:00, then
# a snapshot taken at 8:10, and then a backup at 8:20.
# When taking an incremental backup of the snapshot, the
# parent should be the backup at 8:00, not 8:20, and the
# 'data_timestamp' of this new backup will be 8:10.
latest_backup = max(
backups.objects,
key=lambda x: x['data_timestamp']
if (not snapshot or (snapshot and x['data_timestamp']
< snapshot['created_at']))
else datetime(1, 1, 1, 1, 1, 1, tzinfo=timezone('UTC')))
else:
msg = _('No backups available to do an incremental backup.')
raise exception.InvalidBackup(reason=msg)
@ -229,6 +261,11 @@ class API(base.Base):
'incremental backup.')
raise exception.InvalidBackup(reason=msg)
data_timestamp = None
if snapshot_id:
snapshot = objects.Snapshot.get_by_id(context, snapshot_id)
data_timestamp = snapshot.created_at
self.db.volume_update(context, volume_id,
{'status': 'backing-up',
'previous_status': previous_status})
@ -244,9 +281,14 @@ class API(base.Base):
'parent_id': parent_id,
'size': volume['size'],
'host': volume_host,
'snapshot_id': snapshot_id,
'data_timestamp': data_timestamp,
}
backup = objects.Backup(context=context, **kwargs)
backup.create()
if not snapshot_id:
backup.data_timestamp = backup.created_at
backup.save()
QUOTAS.commit(context, reservations)
except Exception:
with excutils.save_and_reraise_exception():

40
cinder/db/sqlalchemy/migrate_repo/versions/061_add_snapshot_id_timestamp_to_backups.py Normal file
View File

@ -0,0 +1,40 @@
# Copyright (c) 2015 EMC Corporation
# All Rights Reserved.
#
# Licensed under the Apache License, Version 2.0 (the "License"); you may
# not use this file except in compliance with the License. You may obtain
# a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
# License for the specific language governing permissions and limitations
# under the License.
from sqlalchemy import Column, DateTime, MetaData, String, Table
def upgrade(migrate_engine):
meta = MetaData()
meta.bind = migrate_engine
backups = Table('backups', meta, autoload=True)
snapshot_id = Column('snapshot_id', String(length=36))
data_timestamp = Column('data_timestamp', DateTime)
backups.create_column(snapshot_id)
backups.update().values(snapshot_id=None).execute()
backups.create_column(data_timestamp)
backups.update().values(data_timestamp=None).execute()
# Copy existing created_at timestamp to data_timestamp
# in the backups table.
backups_list = list(backups.select().execute())
for backup in backups_list:
backup_id = backup.id
backups.update().\
where(backups.c.id == backup_id).\
values(data_timestamp=backup.created_at).execute()

2
cinder/db/sqlalchemy/models.py
View File

@ -541,6 +541,8 @@ class Backup(BASE, CinderBase):
temp_volume_id = Column(String(36))
temp_snapshot_id = Column(String(36))
num_dependent_backups = Column(Integer)
snapshot_id = Column(String(36))
data_timestamp = Column(DateTime)
@validates('fail_reason')
def validate_fail_reason(self, key, fail_reason):

5
cinder/objects/backup.py
View File

@ -38,7 +38,8 @@ class Backup(base.CinderPersistentObject, base.CinderObject,
# Version 1.0: Initial version
# Version 1.1: Add new field num_dependent_backups and extra fields
# is_incremental and has_dependent_backups.
VERSION = '1.1'
# Version 1.2: Add new field snapshot_id and data_timestamp.
VERSION = '1.2'
fields = {
'id': fields.UUIDField(),
@ -68,6 +69,8 @@ class Backup(base.CinderPersistentObject, base.CinderObject,
'temp_volume_id': fields.StringField(nullable=True),
'temp_snapshot_id': fields.StringField(nullable=True),
'num_dependent_backups': fields.IntegerField(),
'snapshot_id': fields.StringField(nullable=True),
'data_timestamp': fields.DateTimeField(nullable=True),
}
obj_extra_fields = ['name', 'is_incremental', 'has_dependent_backups']

83
cinder/tests/unit/api/contrib/test_backups.py
View File

@ -20,6 +20,7 @@ Tests for Backup code.
import json
from xml.dom import minidom
import ddt
import mock
from oslo_utils import timeutils
import webob
@ -37,7 +38,10 @@ from cinder.tests.unit import utils
# needed for stubs to work
import cinder.volume
NUM_ELEMENTS_IN_BACKUP = 17
@ddt.ddt
class BackupsAPITestCase(test.TestCase):
"""Test Case for backups API."""
@ -55,11 +59,12 @@ class BackupsAPITestCase(test.TestCase):
display_description='this is a test backup',
container='volumebackups',
status='creating',
snapshot=False,
incremental=False,
parent_id=None,
size=0, object_count=0, host='testhost',
num_dependent_backups=0):
num_dependent_backups=0,
snapshot_id=None,
data_timestamp=None):
"""Create a backup object."""
backup = {}
backup['volume_id'] = volume_id
@ -74,21 +79,35 @@ class BackupsAPITestCase(test.TestCase):
backup['fail_reason'] = ''
backup['size'] = size
backup['object_count'] = object_count
backup['snapshot'] = snapshot
backup['incremental'] = incremental
backup['parent_id'] = parent_id
backup['num_dependent_backups'] = num_dependent_backups
return db.backup_create(context.get_admin_context(), backup)['id']
backup['snapshot_id'] = snapshot_id
backup['data_timestamp'] = data_timestamp
backup = db.backup_create(context.get_admin_context(), backup)
if not snapshot_id:
db.backup_update(context.get_admin_context(),
backup['id'],
{'data_timestamp': backup['created_at']})
return backup['id']
@staticmethod
def _get_backup_attrib(backup_id, attrib_name):
return db.backup_get(context.get_admin_context(),
backup_id)[attrib_name]
def test_show_backup(self):
@ddt.data(False, True)
def test_show_backup(self, backup_from_snapshot):
volume_id = utils.create_volume(self.context, size=5,
status='creating')['id']
backup_id = self._create_backup(volume_id)
snapshot = None
snapshot_id = None
if backup_from_snapshot:
snapshot = utils.create_snapshot(self.context,
volume_id)
snapshot_id = snapshot.id
backup_id = self._create_backup(volume_id,
snapshot_id=snapshot_id)
req = webob.Request.blank('/v2/fake/backups/%s' %
backup_id)
req.method = 'GET'
@ -109,8 +128,11 @@ class BackupsAPITestCase(test.TestCase):
self.assertEqual(volume_id, res_dict['backup']['volume_id'])
self.assertFalse(res_dict['backup']['is_incremental'])
self.assertFalse(res_dict['backup']['has_dependent_backups'])
self.assertEqual(snapshot_id, res_dict['backup']['snapshot_id'])
self.assertIn('updated_at', res_dict['backup'])
if snapshot:
snapshot.destroy()
db.backup_destroy(context.get_admin_context(), backup_id)
db.volume_destroy(context.get_admin_context(), volume_id)
@ -283,7 +305,7 @@ class BackupsAPITestCase(test.TestCase):
res_dict = json.loads(res.body)
self.assertEqual(200, res.status_int)
self.assertEqual(15, len(res_dict['backups'][0]))
self.assertEqual(NUM_ELEMENTS_IN_BACKUP, len(res_dict['backups'][0]))
self.assertEqual('az1', res_dict['backups'][0]['availability_zone'])
self.assertEqual('volumebackups',
res_dict['backups'][0]['container'])
@ -298,7 +320,7 @@ class BackupsAPITestCase(test.TestCase):
self.assertEqual('1', res_dict['backups'][0]['volume_id'])
self.assertIn('updated_at', res_dict['backups'][0])
self.assertEqual(15, len(res_dict['backups'][1]))
self.assertEqual(NUM_ELEMENTS_IN_BACKUP, len(res_dict['backups'][1]))
self.assertEqual('az1', res_dict['backups'][1]['availability_zone'])
self.assertEqual('volumebackups',
res_dict['backups'][1]['container'])
@ -313,7 +335,7 @@ class BackupsAPITestCase(test.TestCase):
self.assertEqual('1', res_dict['backups'][1]['volume_id'])
self.assertIn('updated_at', res_dict['backups'][1])
self.assertEqual(15, len(res_dict['backups'][2]))
self.assertEqual(NUM_ELEMENTS_IN_BACKUP, len(res_dict['backups'][2]))
self.assertEqual('az1', res_dict['backups'][2]['availability_zone'])
self.assertEqual('volumebackups', res_dict['backups'][2]['container'])
self.assertEqual('this is a test backup',
@ -469,9 +491,9 @@ class BackupsAPITestCase(test.TestCase):
self.assertEqual(200, res.status_int)
self.assertEqual(2, len(res_dict['backups']))
self.assertEqual(15, len(res_dict['backups'][0]))
self.assertEqual(NUM_ELEMENTS_IN_BACKUP, len(res_dict['backups'][0]))
self.assertEqual(backup_id3, res_dict['backups'][0]['id'])
self.assertEqual(15, len(res_dict['backups'][1]))
self.assertEqual(NUM_ELEMENTS_IN_BACKUP, len(res_dict['backups'][1]))
self.assertEqual(backup_id2, res_dict['backups'][1]['id'])
db.backup_destroy(context.get_admin_context(), backup_id3)
@ -492,9 +514,9 @@ class BackupsAPITestCase(test.TestCase):
self.assertEqual(200, res.status_int)
self.assertEqual(2, len(res_dict['backups']))
self.assertEqual(15, len(res_dict['backups'][0]))
self.assertEqual(NUM_ELEMENTS_IN_BACKUP, len(res_dict['backups'][0]))
self.assertEqual(backup_id2, res_dict['backups'][0]['id'])
self.assertEqual(15, len(res_dict['backups'][1]))
self.assertEqual(NUM_ELEMENTS_IN_BACKUP, len(res_dict['backups'][1]))
self.assertEqual(backup_id1, res_dict['backups'][1]['id'])
db.backup_destroy(context.get_admin_context(), backup_id3)
@ -515,7 +537,7 @@ class BackupsAPITestCase(test.TestCase):
self.assertEqual(200, res.status_int)
self.assertEqual(1, len(res_dict['backups']))
self.assertEqual(15, len(res_dict['backups'][0]))
self.assertEqual(NUM_ELEMENTS_IN_BACKUP, len(res_dict['backups'][0]))
self.assertEqual(backup_id2, res_dict['backups'][0]['id'])
db.backup_destroy(context.get_admin_context(), backup_id3)
@ -683,14 +705,22 @@ class BackupsAPITestCase(test.TestCase):
@mock.patch('cinder.db.service_get_all_by_topic')
@mock.patch(
'cinder.api.openstack.wsgi.Controller.validate_name_and_description')
def test_create_backup_delta(self, mock_validate,
@ddt.data(False, True)
def test_create_backup_delta(self, backup_from_snapshot,
mock_validate,
_mock_service_get_all_by_topic):
_mock_service_get_all_by_topic.return_value = [
{'availability_zone': "fake_az", 'host': 'test_host',
'disabled': 0, 'updated_at': timeutils.utcnow()}]
volume_id = utils.create_volume(self.context, size=5)['id']
snapshot = None
snapshot_id = None
if backup_from_snapshot:
snapshot = utils.create_snapshot(self.context,
volume_id,
status='available')
snapshot_id = snapshot.id
backup_id = self._create_backup(volume_id, status="available")
body = {"backup": {"display_name": "nightly001",
"display_description":
@ -698,6 +728,7 @@ class BackupsAPITestCase(test.TestCase):
"volume_id": volume_id,
"container": "nightlybackups",
"incremental": True,
"snapshot_id": snapshot_id,
}
}
req = webob.Request.blank('/v2/fake/backups')
@ -713,6 +744,8 @@ class BackupsAPITestCase(test.TestCase):
self.assertTrue(mock_validate.called)
db.backup_destroy(context.get_admin_context(), backup_id)
if snapshot:
snapshot.destroy()
db.volume_destroy(context.get_admin_context(), volume_id)
@mock.patch('cinder.db.service_get_all_by_topic')
@ -1932,7 +1965,8 @@ class BackupsAPITestCase(test.TestCase):
self.assertRaises(exception.NotSupportedOperation,
self.backup_api.delete, self.context, backup, True)
def test_show_incremental_backup(self):
@ddt.data(False, True)
def test_show_incremental_backup(self, backup_from_snapshot):
volume_id = utils.create_volume(self.context, size=5)['id']
parent_backup_id = self._create_backup(volume_id, status="available",
num_dependent_backups=1)
@ -1940,9 +1974,16 @@ class BackupsAPITestCase(test.TestCase):
incremental=True,
parent_id=parent_backup_id,
num_dependent_backups=1)
snapshot = None
snapshot_id = None
if backup_from_snapshot:
snapshot = utils.create_snapshot(self.context,
volume_id)
snapshot_id = snapshot.id
child_backup_id = self._create_backup(volume_id, status="available",
incremental=True,
parent_id=backup_id)
parent_id=backup_id,
snapshot_id=snapshot_id)
req = webob.Request.blank('/v2/fake/backups/%s' %
backup_id)
@ -1954,6 +1995,7 @@ class BackupsAPITestCase(test.TestCase):
self.assertEqual(200, res.status_int)
self.assertTrue(res_dict['backup']['is_incremental'])
self.assertTrue(res_dict['backup']['has_dependent_backups'])
self.assertIsNone(res_dict['backup']['snapshot_id'])
req = webob.Request.blank('/v2/fake/backups/%s' %
parent_backup_id)
@ -1965,6 +2007,7 @@ class BackupsAPITestCase(test.TestCase):
self.assertEqual(200, res.status_int)
self.assertFalse(res_dict['backup']['is_incremental'])
self.assertTrue(res_dict['backup']['has_dependent_backups'])
self.assertIsNone(res_dict['backup']['snapshot_id'])
req = webob.Request.blank('/v2/fake/backups/%s' %
child_backup_id)
@ -1976,7 +2019,11 @@ class BackupsAPITestCase(test.TestCase):
self.assertEqual(200, res.status_int)
self.assertTrue(res_dict['backup']['is_incremental'])
self.assertFalse(res_dict['backup']['has_dependent_backups'])
self.assertEqual(snapshot_id, res_dict['backup']['snapshot_id'])
db.backup_destroy(context.get_admin_context(), child_backup_id)
db.backup_destroy(context.get_admin_context(), backup_id)
db.backup_destroy(context.get_admin_context(), parent_backup_id)
if snapshot:
snapshot.destroy()
db.volume_destroy(context.get_admin_context(), volume_id)

7
cinder/tests/unit/objects/test_backup.py
View File

@ -33,6 +33,8 @@ fake_backup = {
'project_id': 'fake_project',
'temp_volume_id': None,
'temp_snapshot_id': None,
'snapshot_id': None,
'data_timestamp': None,
}
@ -85,6 +87,11 @@ class TestBackup(test_objects.BaseObjectsTestCase):
self.assertEqual('2', backup.temp_volume_id)
self.assertEqual('3', backup.temp_snapshot_id)
def test_obj_field_snapshot_id(self):
backup = objects.Backup(context=self.context,
snapshot_id='2')
self.assertEqual('2', backup.snapshot_id)
def test_import_record(self):
utils.replace_obj_loader(self, objects.Backup)
backup = objects.Backup(context=self.context, id=1, parent_id=None,

4
cinder/tests/unit/objects/test_objects.py
View File

@ -21,8 +21,8 @@ from cinder import test
# NOTE: The hashes in this list should only be changed if they come with a
# corresponding version bump in the affected objects.
object_data = {
'Backup': '1.1-cd077ec037f5ad1f5409fd660bd59f53',
'BackupImport': '1.1-cd077ec037f5ad1f5409fd660bd59f53',
'Backup': '1.2-62c3da6df3dccb76796e4da65a45a44f',
'BackupImport': '1.2-62c3da6df3dccb76796e4da65a45a44f',
'BackupList': '1.0-24591dabe26d920ce0756fe64cd5f3aa',
'CGSnapshot': '1.0-190da2a2aa9457edc771d888f7d225c4',
'CGSnapshotList': '1.0-e8c3f4078cd0ee23487b34d173eec776',

6
cinder/tests/unit/test_db_api.py
View File

@ -1901,7 +1901,8 @@ class DBAPIBackupTestCase(BaseTest):
"""Tests for db.api.backup_* methods."""
_ignored_keys = ['id', 'deleted', 'deleted_at', 'created_at', 'updated_at']
_ignored_keys = ['id', 'deleted', 'deleted_at', 'created_at',
'updated_at', 'data_timestamp']
def setUp(self):
super(DBAPIBackupTestCase, self).setUp()
@ -1927,7 +1928,8 @@ class DBAPIBackupTestCase(BaseTest):
'object_count': 100,
'temp_volume_id': 'temp_volume_id',
'temp_snapshot_id': 'temp_snapshot_id',
'num_dependent_backups': 0, }
'num_dependent_backups': 0,
'snapshot_id': 'snapshot_id', }
if one:
return base_values

7
cinder/tests/unit/test_migrations.py
View File

@ -710,6 +710,13 @@ class MigrationsMixin(test_migrations.WalkVersionsMixin):
self.assertIsInstance(private_data.c.last_used.type,
self.TIME_TYPE)
def _check_061(self, engine, data):
backups = db_utils.get_table(engine, 'backups')
self.assertIsInstance(backups.c.snapshot_id.type,
sqlalchemy.types.VARCHAR)
self.assertIsInstance(backups.c.data_timestamp.type,
self.TIME_TYPE)
def test_walk_versions(self):
self.walk_versions(False, False)

1
cinder/tests/unit/test_volume_utils.py
View File

@ -385,6 +385,7 @@ class NotifyUsageTestCase(test.TestCase):
'fail_reason': None,
'parent_id': 'fake_parent_id',
'num_dependent_backups': 0,
'snapshot_id': None,
}
# Make it easier to find out differences between raw and expected.

6
cinder/tests/unit/utils.py
View File

@ -171,7 +171,9 @@ def create_backup(ctxt,
status='creating',
parent_id=None,
temp_volume_id=None,
temp_snapshot_id=None):
temp_snapshot_id=None,
snapshot_id=None,
data_timestamp=None):
backup = {}
backup['volume_id'] = volume_id
backup['user_id'] = ctxt.user_id
@ -189,6 +191,8 @@ def create_backup(ctxt,
backup['object_count'] = 22
backup['temp_volume_id'] = temp_volume_id
backup['temp_snapshot_id'] = temp_snapshot_id
backup['snapshot_id'] = snapshot_id
backup['data_timestamp'] = data_timestamp
return db.backup_create(ctxt, backup)

93
cinder/volume/driver.py
View File

@ -1073,6 +1073,15 @@ class BaseVD(object):
def backup_volume(self, context, backup, backup_service):
"""Create a new backup from an existing volume."""
# NOTE(xyang): _backup_volume_temp_snapshot and
# _backup_volume_temp_volume are splitted into two
# functions because there were concerns during code
# reviews that it is confusing to put all the logic
# into one function. There's a trade-off between
# reducing code duplication and increasing code
# readability here. Added a note here to explain why
# we've decided to have two separate functions as
# there will always be arguments from both sides.
if self.backup_use_temp_snapshot():
self._backup_volume_temp_snapshot(context, backup,
backup_service)
@ -1081,21 +1090,40 @@ class BaseVD(object):
backup_service)
def _backup_volume_temp_volume(self, context, backup, backup_service):
"""Create a new backup from an existing volume.
"""Create a new backup from an existing volume or snapshot.
For in-use volume, create a temp volume and back it up.
To backup a snapshot, create a temp volume from the snapshot and
back it up.
Otherwise to backup an in-use volume, create a temp volume and
back it up.
"""
volume = self.db.volume_get(context, backup.volume_id)
snapshot = None
if backup.snapshot_id:
snapshot = objects.Snapshot.get_by_id(context, backup.snapshot_id)
LOG.debug('Creating a new backup for volume %s.', volume['name'])
# NOTE(xyang): Check volume status; if 'in-use', create a temp
# volume from the source volume, backup the temp volume, and
# then clean up the temp volume; if 'available', just backup the
# volume.
previous_status = volume.get('previous_status', None)
device_to_backup = volume
temp_vol_ref = None
device_to_backup = volume
# NOTE(xyang): If it is to backup from snapshot, create a temp
# volume from the source snapshot, backup the temp volume, and
# then clean up the temp volume.
if snapshot:
temp_vol_ref = self._create_temp_volume_from_snapshot(
context, volume, snapshot)
backup.temp_volume_id = temp_vol_ref['id']
backup.save()
device_to_backup = temp_vol_ref
else:
# NOTE(xyang): Check volume status if it is not to backup from
# snapshot; if 'in-use', create a temp volume from the source
# volume, backup the temp volume, and then clean up the temp
# volume; if 'available', just backup the volume.
previous_status = volume.get('previous_status')
if previous_status == "in-use":
temp_vol_ref = self._create_temp_cloned_volume(
context, volume)
@ -1111,22 +1139,36 @@ class BaseVD(object):
backup.save()
def _backup_volume_temp_snapshot(self, context, backup, backup_service):
"""Create a new backup from an existing volume.
"""Create a new backup from an existing volume or snapshot.
For in-use volume, create a temp snapshot and back it up.
If it is to backup from snapshot, back it up directly.
Otherwise for in-use volume, create a temp snapshot and back it up.
"""
volume = self.db.volume_get(context, backup.volume_id)
snapshot = None
if backup.snapshot_id:
snapshot = objects.Snapshot.get_by_id(context, backup.snapshot_id)
LOG.debug('Creating a new backup for volume %s.', volume['name'])
# NOTE(xyang): Check volume status; if 'in-use', create a temp
# snapshot from the source volume, backup the temp snapshot, and
# then clean up the temp snapshot; if 'available', just backup the
# volume.
previous_status = volume.get('previous_status', None)
device_to_backup = volume
is_snapshot = False
temp_snapshot = None
# NOTE(xyang): If it is to backup from snapshot, back it up
# directly. No need to clean it up.
if snapshot:
device_to_backup = snapshot
is_snapshot = True
else:
# NOTE(xyang): If it is not to backup from snapshot, check volume
# status. If the volume status is 'in-use', create a temp snapshot
# from the source volume, backup the temp snapshot, and then clean
# up the temp snapshot; if the volume status is 'available', just
# backup the volume.
previous_status = volume.get('previous_status')
if previous_status == "in-use":
temp_snapshot = self._create_temp_snapshot(context, volume)
backup.temp_snapshot_id = temp_snapshot.id
@ -1255,6 +1297,27 @@ class BaseVD(object):
{'status': 'available'})
return temp_vol_ref
def _create_temp_volume_from_snapshot(self, context, volume, snapshot):
temp_volume = {
'size': volume['size'],
'display_name': 'backup-vol-%s' % volume['id'],
'host': volume['host'],
'user_id': context.user_id,
'project_id': context.project_id,
'status': 'creating',
}
temp_vol_ref = self.db.volume_create(context, temp_volume)
try:
self.create_volume_from_snapshot(temp_vol_ref, snapshot)
except Exception:
with excutils.save_and_reraise_exception():
self.db.volume_destroy(context.elevated(),
temp_vol_ref['id'])
self.db.volume_update(context, temp_vol_ref['id'],
{'status': 'available'})
return temp_vol_ref
def _delete_temp_snapshot(self, context, snapshot):
self.delete_snapshot(snapshot)
with snapshot.obj_as_admin():

18
cinder/volume/drivers/lvm.py
View File

@ -31,6 +31,7 @@ from cinder.brick.local_dev import lvm as lvm
from cinder import exception
from cinder.i18n import _, _LE, _LI, _LW
from cinder.image import image_utils
from cinder import objects
from cinder import utils
from cinder.volume import driver
from cinder.volume import utils as volutils
@ -505,9 +506,22 @@ class LVMVolumeDriver(driver.VolumeDriver):
def backup_volume(self, context, backup, backup_service):
"""Create a new backup from an existing volume."""
volume = self.db.volume_get(context, backup.volume_id)
snapshot = None
if backup.snapshot_id:
snapshot = objects.Snapshot.get_by_id(context, backup.snapshot_id)
temp_snapshot = None
previous_status = volume['previous_status']
if previous_status == 'in-use':
# NOTE(xyang): If it is to backup from snapshot, back it up
# directly. No need to clean it up.
if snapshot:
volume_path = self.local_path(snapshot)
else:
# NOTE(xyang): If it is not to backup from snapshot, check volume
# status. If the volume status is 'in-use', create a temp snapshot
# from the source volume, backup the temp snapshot, and then clean
# up the temp snapshot; if the volume status is 'available', just
# backup the volume.
previous_status = volume.get('previous_status', None)
if previous_status == "in-use":
temp_snapshot = self._create_temp_snapshot(context, volume)
backup.temp_snapshot_id = temp_snapshot.id
backup.save()

1
cinder/volume/utils.py
View File

@ -108,6 +108,7 @@ def _usage_from_backup(backup_ref, **kw):
fail_reason=backup_ref['fail_reason'],
parent_id=backup_ref['parent_id'],
num_dependent_backups=num_dependent_backups,
snapshot_id=backup_ref['snapshot_id'],
)
usage_info.update(kw)

3
releasenotes/notes/backup-snapshots-2f547c8788bc11e1.yaml Normal file
View File

@ -0,0 +1,3 @@
---
features:
- Backup snapshots.