openstack/cinder
Code Issues Proposed changes

Add the iscsi device check and exception processing.

Browse Source 
Before downloading the image and executing the command "qemu-img convert",
check if the iSCSI device is still available via the command "sudo dd
if=<device> of=/dev/null count=1". This command will raise an exception with
the message "Input/output error", if the back-end storage is disconnected to
the cinder-volume node, so we use it to test the availability of the storage
device. If it is unavailable, there is no need to download the image &
"qemu-img convert" and an exception DeviceUnavailable will be raised.

Fixed Bug1169290.

Change-Id: I133b4cc1bac493df073d42e240092cf2e6300454
This commit is contained in:
Vincent Hou 2013-06-06 16:46:52 +08:00
parent b820205c73
commit aa7fde57a3
3 changed files with 86 additions and 25 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

4
cinder/exception.py
View File

@ -194,6 +194,10 @@ class ImageUnacceptable(Invalid):
message = _("Image %(image_id)s is unacceptable: %(reason)s")
class DeviceUnavailable(Invalid):
message = _("The device in the path %(path)s is unavailable: %(reason)s")
class InvalidUUID(Invalid):
message = _("Expected a uuid but received %(uuid)s.")

105
cinder/volume/driver.py
View File

@ -310,6 +310,16 @@ class ISCSIDriver(VolumeDriver):
(iscsi_command, out, err))
return (out, err)
def _run_iscsiadm_bare(self, iscsi_command, **kwargs):
check_exit_code = kwargs.pop('check_exit_code', 0)
(out, err) = utils.execute('iscsiadm',
*iscsi_command,
run_as_root=True,
check_exit_code=check_exit_code)
LOG.debug("iscsiadm %s: stdout=%s stderr=%s" %
(iscsi_command, out, err))
return (out, err)
def _iscsiadm_update(self, iscsi_properties, property_key, property_value,
**kwargs):
iscsi_command = ('--op', 'update', '-n', property_key,
@ -347,6 +357,22 @@ class ISCSIDriver(VolumeDriver):
def terminate_connection(self, volume, connector, **kwargs):
pass
def _check_valid_device(self, path):
cmd = ('dd', 'if=%(path)s' % {"path": path},
'of=/dev/null', 'count=1')
out, info = None, None
try:
out, info = utils.execute(*cmd, run_as_root=True)
except exception.ProcessExecutionError as e:
LOG.error(_("Failed to access the device on the path "
"%(path)s: %(error)s.") %
{"path": path, "error": e.stderr})
return False
# If the info is none, the path does not exist.
if info is None:
return False
return True
def _get_iscsi_initiator(self):
"""Get iscsi initiator name for this machine"""
# NOTE openiscsi stores initiator name in a file that
@ -418,40 +444,71 @@ class ISCSIDriver(VolumeDriver):
"node.session.auth.password",
iscsi_properties['auth_password'])
# NOTE(vish): If we have another lun on the same target, we may
# have a duplicate login
self._run_iscsiadm(iscsi_properties, ("--login",),
check_exit_code=[0, 255])
self._iscsiadm_update(iscsi_properties, "node.startup", "automatic")
host_device = ("/dev/disk/by-path/ip-%s-iscsi-%s-lun-%s" %
(iscsi_properties['target_portal'],
iscsi_properties['target_iqn'],
iscsi_properties.get('target_lun', 0)))
tries = 0
while not os.path.exists(host_device):
if tries >= self.configuration.num_iscsi_scan_tries:
raise exception.CinderException(
_("iSCSI device not found at %s") % (host_device))
out = self._run_iscsiadm_bare(["-m", "session"],
run_as_root=True,
check_exit_code=[0, 1, 21])[0] or ""
LOG.warn(_("ISCSI volume not yet found at: %(host_device)s. "
"Will rescan & retry. Try number: %(tries)s") %
locals())
portals = [{'portal': p.split(" ")[2], 'iqn': p.split(" ")[3]}
for p in out.splitlines() if p.startswith("tcp:")]
# The rescan isn't documented as being necessary(?), but it helps
self._run_iscsiadm(iscsi_properties, ("--rescan",))
stripped_portal = iscsi_properties['target_portal'].split(",")[0]
length_iqn = [s for s in portals
if stripped_portal ==
s['portal'].split(",")[0] and
s['iqn'] == iscsi_properties['target_iqn']]
if len(portals) == 0 or len(length_iqn) == 0:
try:
self._run_iscsiadm(iscsi_properties, ("--login",),
check_exit_code=[0, 255])
except exception.ProcessExecutionError as err:
if err.exit_code in [15]:
self._iscsiadm_update(iscsi_properties,
"node.startup",
"automatic")
return iscsi_properties, host_device
else:
raise
tries = tries + 1
if not os.path.exists(host_device):
time.sleep(tries ** 2)
self._iscsiadm_update(iscsi_properties,
"node.startup", "automatic")
if tries != 0:
LOG.debug(_("Found iSCSI node %(host_device)s "
"(after %(tries)s rescans)") %
locals())
tries = 0
while not os.path.exists(host_device):
if tries >= self.configuration.num_iscsi_scan_tries:
raise exception.CinderException(_("iSCSI device "
"not found "
"at %s") % (host_device))
LOG.warn(_("ISCSI volume not yet found at: %(host_device)s. "
"Will rescan & retry. Try number: %(tries)s.") %
{'host_device': host_device, 'tries': tries})
# The rescan isn't documented as being necessary(?),
# but it helps
self._run_iscsiadm(iscsi_properties, ("--rescan",))
tries = tries + 1
if not os.path.exists(host_device):
time.sleep(tries ** 2)
if tries != 0:
LOG.debug(_("Found iSCSI node %(host_device)s "
"(after %(tries)s rescans).") %
{'host_device': host_device,
'tries': tries})
if not self._check_valid_device(host_device):
raise exception.DeviceUnavailable(path=host_device,
reason=(_("Unable to access "
"the backend storage "
"via the path "
"%(path)s.") %
{'path': host_device}))
return iscsi_properties, host_device
def get_volume_stats(self, refresh=False):

2
cinder/volume/manager.py
View File

@ -615,7 +615,7 @@ class VolumeManager(manager.SchedulerDependentManager):
"error: %(error)s") % {'volume_id': volume_id,
'error': ex.stderr})
raise exception.ImageCopyFailure(reason=ex.stderr)
except exception.ImageUnacceptable as ex:
except Exception as ex:
LOG.error(_("Failed to copy image to volume: %(volume_id)s, "
"error: %(error)s") % {'volume_id': volume_id,
'error': ex})