openstack/cinder
Code Issues Proposed changes

RBD: add support for active/active replication

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This patch breaks failover_host into the two requisite parts (failover
and failover_completed) to support both single-backend and multiple
backends configured as active/active.

Change-Id: Ie59ba9ad538b2e607dd7ccabc0fbb035a6acf3b0
This commit is contained in:
Jon Bernard 2018-03-22 08:09:35 -07:00
parent bc142cca6c
commit 245a488c36
3 changed files with 32 additions and 5 deletions
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2
cinder/tests/unit/volume/drivers/test_rbd.py
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@ -1804,7 +1804,7 @@ class RBDTestCase(test.TestCase):
[mock.call(mock.ANY, v, remote, False,
fields.ReplicationStatus.FAILED_OVER)
for v in volumes])
mock_get_cfg.assert_called_once_with(secondary_id)
mock_get_cfg.assert_called_with(secondary_id)
@mock.patch.object(driver.RBDDriver, '_failover_volume', autospec=True)
def test_failover_host_failback(self, mock_failover_vol):

30
cinder/volume/drivers/rbd.py
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@ -200,6 +200,8 @@ class RBDDriver(driver.CloneableImageVD, driver.MigrateVD,
# ThirdPartySystems wiki page
CI_WIKI_NAME = "Cinder_Jenkins"
SUPPORTS_ACTIVE_ACTIVE = True
SYSCONFDIR = '/etc/ceph/'
def __init__(self, active_backend_id=None, *args, **kwargs):
@ -1185,8 +1187,8 @@ class RBDDriver(driver.CloneableImageVD, driver.MigrateVD,
secondary_id = candidates.pop()
return secondary_id, self._get_target_config(secondary_id)
def failover_host(self, context, volumes, secondary_id=None, groups=None):
"""Failover to replication target."""
def failover(self, context, volumes, secondary_id=None, groups=None):
"""Failover replicated volumes."""
LOG.info('RBD driver failover started.')
if not self._is_replication_enabled:
raise exception.UnableToFailOver(
@ -1201,15 +1203,35 @@ class RBDDriver(driver.CloneableImageVD, driver.MigrateVD,
# Try to demote the volumes first
demotion_results = self._demote_volumes(volumes)
# Do the failover taking into consideration if they have been demoted
updates = [self._failover_volume(volume, remote, is_demoted,
replication_status)
for volume, is_demoted in zip(volumes, demotion_results)]
self._active_backend_id = secondary_id
self._active_config = remote
LOG.info('RBD driver failover completed.')
return secondary_id, updates, []
def failover_completed(self, context, secondary_id=None):
"""Failover to replication target."""
LOG.info('RBD driver failover completion started.')
secondary_id, remote = self._get_failover_target_config(secondary_id)
self._active_backend_id = secondary_id
self._active_config = remote
LOG.info('RBD driver failover completion completed.')
def failover_host(self, context, volumes, secondary_id=None, groups=None):
"""Failover to replication target.
This function combines calls to failover() and failover_completed() to
perform failover when Active/Active is not enabled.
"""
active_backend_id, volume_update_list, group_update_list = (
self.failover(context, volumes, secondary_id, groups))
self.failover_completed(context, secondary_id)
return active_backend_id, volume_update_list, group_update_list
def ensure_export(self, context, volume):
"""Synchronously recreates an export for a logical volume."""
pass

5
releasenotes/notes/rbd-active-active-replication-b230367912fe4a23.yaml Normal file
View File

@ -0,0 +1,5 @@
---
features:
- Added support for active-active replication to the RBD driver. This allows
users to configure multiple volume backends that are all a member of the
same cluster participating in replication.