openstack nova essex-4でのvolume attachに関連するコード nova/nova/compute/manager.py 1656 def attach_volume(self, context, instance_uuid, volume_id, mountpoint): 1657 """Attach a volume to an instance.""" 1658 volume = self.volume_api.get(conte

gistfile1.py

nova/nova/compute/manager.py
1656     def attach_volume(self, context, instance_uuid, volume_id, mountpoint):
1657         """Attach a volume to an instance."""
1658         volume = self.volume_api.get(context, volume_id)
1659         context = context.elevated()
1660         instance_ref = self.db.instance_get_by_uuid(context, instance_uuid)
1661         instance_id = instance_ref['id']
1662         msg = _("instance %(instance_uuid)s: attaching volume %(volume_id)s"
1663                 " to %(mountpoint)s")
1664         LOG.audit(_('Attaching volume %(volume_id)s to %(mountpoint)s'),
1665                   locals(), context=context, instance=instance_ref)
1666         try:
1667             connector = self.driver.get_volume_connector(instance_ref)
1668             connection_info = self.volume_api.initialize_connection(context,
1669                                                                     volume,
1670                                                                     connector)
1671         except Exception:  # pylint: disable=W0702
1672             with utils.save_and_reraise_exception():
1673                 msg = _("instance %(instance_uuid)s: attach failed"
1674                         " %(mountpoint)s, removing")
1675                 LOG.exception(msg % locals(), context=context)
1676                 self.volume_api.unreserve_volume(context, volume)
1677         try:
1678             self.driver.attach_volume(connection_info,	         #<-----ここでatttachしている
1679                                       instance_ref['name'],
1680                                       mountpoint)
1681         except Exception:  # pylint: disable=W0702
1682             with utils.save_and_reraise_exception():
1683                 LOG.exception(_('Attach failed %(mountpoint)s, removing'),
1684                               locals(), context=context,
1685                               instance=instance_ref)
1686                 self.volume_api.terminate_connection(context,
1687                                                      volume,
1688                                                      connector)
1689 
1690         self.volume_api.attach(context, volume, instance_id, mountpoint)
1691         values = {
1692             'instance_id': instance_id,
1693             'connection_info': utils.dumps(connection_info),
1694             'device_name': mountpoint,
1695             'delete_on_termination': False,
1696             'virtual_name': None,
1697             'snapshot_id': None,
1698             'volume_id': volume_id,
1699             'volume_size': None,
1700             'no_device': None}
1701         self.db.block_device_mapping_create(context, values)
1702         return True


nova/nova/virt/libvirt/connection.py
 463     @exception.wrap_exception()
 464     def attach_volume(self, connection_info, instance_name, mountpoint):
 465         virt_dom = self._lookup_by_name(instance_name)
 466         mount_device = mountpoint.rpartition("/")[2]
 467         xml = self.volume_driver_method('connect_volume',   #<----connect_volume でvolume情報を取得
 468                                         connection_info,
 469                                         mount_device)
 470 
 471         if FLAGS.libvirt_type == 'lxc':
 472             self._attach_lxc_volume(xml, virt_dom, instance_name)
 473         else:
 474             try:
 475                 virt_dom.attachDevice(xml)   #<----ここでlibvirt経由でdeviceを追加している
 476             except Exception, ex:
 477                 self.volume_driver_method('disconnect_volume',
 478                                            connection_info,
 479                                            mount_device)
 480 
 481                 if isinstance(ex, libvirt.libvirtError):
 482                     errcode = ex.get_error_code()
 483                     if errcode == libvirt.VIR_ERR_OPERATION_FAILED:
 484                         raise exception.DeviceIsBusy(device=mount_device)
 485                 raise


nova/nova/virt/libvirt/volume.py
106     @utils.synchronized('connect_volume')
107     def connect_volume(self, connection_info, mount_device):
108         """Attach the volume to instance_name"""
109         iscsi_properties = connection_info['data']
110         # NOTE(vish): If we are on the same host as nova volume, the
111         #             discovery makes the target so we don't need to
112         #             run --op new. Therefore, we check to see if the
113         #             target exists, and if we get 255 (Not Found), then
114         #             we run --op new. This will also happen if another
115         #             volume is using the same target.
116         try:
117             self._run_iscsiadm(iscsi_properties, ())
118         except exception.ProcessExecutionError as exc:
119             # iscsiadm returns 21 for "No records found" after version 2.0-871
120             if exc.exit_code in [21, 255]:
121                 self._run_iscsiadm(iscsi_properties, ('--op', 'new'))
122             else:
123                 raise
124 
125         if iscsi_properties.get('auth_method'):
126             self._iscsiadm_update(iscsi_properties,
127                                   "node.session.auth.authmethod",
128                                   iscsi_properties['auth_method'])
129             self._iscsiadm_update(iscsi_properties,
130                                   "node.session.auth.username",
131                                   iscsi_properties['auth_username'])
132             self._iscsiadm_update(iscsi_properties,
133                                   "node.session.auth.password",
134                                   iscsi_properties['auth_password'])
135 
136         # NOTE(vish): If we have another lun on the same target, we may
137         #             have a duplicate login
138         self._run_iscsiadm(iscsi_properties, ("--login",),
139                            check_exit_code=[0, 255])
140 
141         self._iscsiadm_update(iscsi_properties, "node.startup", "automatic")
142 
143         host_device = ("/dev/disk/by-path/ip-%s-iscsi-%s-lun-%s" %
144                         (iscsi_properties['target_portal'],
145                          iscsi_properties['target_iqn'],
146                          iscsi_properties.get('target_lun', 0)))
147 
148         # The /dev/disk/by-path/... node is not always present immediately
149         # TODO(justinsb): This retry-with-delay is a pattern, move to utils?
150         tries = 0
151         while not os.path.exists(host_device):
152             if tries >= FLAGS.num_iscsi_scan_tries:
153                 raise exception.Error(_("iSCSI device not found at %s") %
154                                       (host_device))
155 
156             LOG.warn(_("ISCSI volume not yet found at: %(mount_device)s. "
157                        "Will rescan & retry.  Try number: %(tries)s") %
158                      locals())
159 
160             # The rescan isn't documented as being necessary(?), but it helps
161             self._run_iscsiadm(iscsi_properties, ("--rescan",))
162 
163             tries = tries + 1
164             if not os.path.exists(host_device):
165                 time.sleep(tries ** 2)
166 
167         if tries != 0:
168             LOG.debug(_("Found iSCSI node %(mount_device)s "
169                         "(after %(tries)s rescans)") %
170                       locals())
171 
172         connection_info['data']['device_path'] = host_device
173         sup = super(LibvirtISCSIVolumeDriver, self)
174         return sup.connect_volume(connection_info, mount_device)