openstack
/
os-brick
Code Issues Proposed changes

Retry multipath flush when map is in use 

When flushing a multipath we are ignoring map in use transient error, so
we log a warning that the flush has not been successful and that we have
received an exit code 1 and we continue to remove the individual paths.

This error is usually transient and a simple retry will succeed in
flushing the multipath.

Failure to retry will leave an empty multipath in our system.

Closes-Bug: #1663936
Change-Id: I710792bd707ad933ef60d11d25f530dddfb6fb2f
This commit is contained in:
Gorka Eguileor 2017-02-11 21:40:39 +01:00
parent c0640ce137
commit 32c837dacb
2 changed files with 23 additions and 0 deletions
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4
os_brick/initiator/linuxscsi.py
View File

@ -150,12 +150,16 @@ class LinuxSCSI(executor.Executor):
LOG.warning(_LW("Failed to flush IO buffers prior to removing "
"device: %(code)s"), {'code': exc.exit_code})
@utils.retry(exceptions=putils.ProcessExecutionError)
def flush_multipath_device(self, device):
try:
LOG.debug("Flush multipath device %s", device)
self._execute('multipath', '-f', device, run_as_root=True,
root_helper=self._root_helper)
except putils.ProcessExecutionError as exc:
if exc.exit_code == 1 and 'map in use' in exc.stdout:
LOG.debug('Multipath is in use, cannot be flushed yet.')
raise
LOG.warning(_LW("multipath call failed exit %(code)s"),
{'code': exc.exit_code})

19
os_brick/tests/initiator/test_linuxscsi.py
View File

@ -18,6 +18,7 @@ import textwrap
import time
import mock
from oslo_concurrency import processutils as putils
from oslo_log import log as logging
from os_brick import exception
@ -95,6 +96,24 @@ class LinuxSCSITestCase(base.TestCase):
expected_commands = [('multipath -f /dev/dm-9')]
self.assertEqual(expected_commands, self.cmds)
@mock.patch('retrying.time.sleep', mock.Mock())
def test_flush_multipath_device_in_use(self):
side_effect = (
putils.ProcessExecutionError(
stdout='Feb 09 14:38:02 | mpatha: map in use\n'
'Feb 09 14:38:02 | failed to remove multipath map '
'mpatha\n',
exit_code=1),
('', '')
)
with mock.patch.object(self.linuxscsi, '_execute') as execute_mock:
execute_mock.side_effect = side_effect
self.linuxscsi.flush_multipath_device('mpatha')
execute_mock.assert_has_calls(
[mock.call('multipath', '-f', 'mpatha', run_as_root=True,
root_helper=mock.ANY)] * 2)
def test_flush_multipath_devices(self):
self.linuxscsi.flush_multipath_devices()
expected_commands = [('multipath -F')]