Fixed a problem in iSCSI multipath

Multipathing during copy image to volume and copy volume to image
operations doesn't work properly if there are different targets
associated with different portals for a mulitpath device.

Change-Id: I65c93f3788020c944db0d3a55063a6415554ff11
Closes-Bug: #1266048

diff --git a/cinder/brick/initiator/connector.py b/cinder/brick/initiator/connector.py
index 996318383d9f24d10e632aebb6d1d2d3e1bed20a..3ffc6b5901396bae0b6ed46ff2c9aa79961a437e 100644 (file)
--- a/cinder/brick/initiator/connector.py
+++ b/cinder/brick/initiator/connector.py
@@ -207,9 +207,10 @@ class ISCSIConnector(InitiatorConnector):
                                           check_exit_code=[0, 255])[0] \
                 or ""
 
-            for ip in self._get_target_portals_from_iscsiadm_output(out):
+            for ip, iqn in self._get_target_portals_from_iscsiadm_output(out):
                 props = connection_properties.copy()
                 props['target_portal'] = ip
+                props['target_iqn'] = iqn
                 self._connect_to_iscsi_portal(props)
 
             self._rescan_iscsi()
@@ -261,12 +262,20 @@ class ISCSIConnector(InitiatorConnector):
         target_iqn - iSCSI Qualified Name
         target_lun - LUN id of the volume
         """
+        # Moved _rescan_iscsi and _rescan_multipath
+        # from _disconnect_volume_multipath_iscsi to here.
+        # Otherwise, if we do rescan after _linuxscsi.remove_multipath_device
+        # but before logging out, the removed devices under /dev/disk/by-path
+        # will reappear after rescan.
+        self._rescan_iscsi()
         host_device = self._get_device_path(connection_properties)
         multipath_device = None
         if self.use_multipath:
+            self._rescan_multipath()
             multipath_device = self._get_multipath_device_name(host_device)
             if multipath_device:
-                self._linuxscsi.remove_multipath_device(multipath_device)
+                device_realpath = os.path.realpath(host_device)
+                self._linuxscsi.remove_multipath_device(device_realpath)
                 return self._disconnect_volume_multipath_iscsi(
                     connection_properties, multipath_device)
 
@@ -331,14 +340,13 @@ class ISCSIConnector(InitiatorConnector):
                                   **kwargs)
 
     def _get_target_portals_from_iscsiadm_output(self, output):
-        return [line.split()[0] for line in output.splitlines()]
+        # return both portals and iqns
+        return [line.split() for line in output.splitlines()]
 
     def _disconnect_volume_multipath_iscsi(self, connection_properties,
                                            multipath_name):
         """This removes a multipath device and it's LUNs."""
         LOG.debug("Disconnect multipath device %s" % multipath_name)
-        self._rescan_iscsi()
-        self._rescan_multipath()
         block_devices = self.driver.get_all_block_devices()
         devices = []
         for dev in block_devices:
@@ -349,17 +357,42 @@ class ISCSIConnector(InitiatorConnector):
                 if mpdev:
                     devices.append(mpdev)
 
+        # Do a discovery to find all targets.
+        # Targets for multiple paths for the same multipath device
+        # may not be the same.
+        out = self._run_iscsiadm_bare(['-m',
+                                      'discovery',
+                                      '-t',
+                                      'sendtargets',
+                                      '-p',
+                                      connection_properties['target_portal']],
+                                      check_exit_code=[0, 255])[0] \
+            or ""
+
+        ips_iqns = self._get_target_portals_from_iscsiadm_output(out)
+
         if not devices:
             # disconnect if no other multipath devices
-            self._disconnect_mpath(connection_properties)
+            self._disconnect_mpath(connection_properties, ips_iqns)
             return
 
+        # Get a target for all other multipath devices
         other_iqns = [self._get_multipath_iqn(device)
                       for device in devices]
-
-        if connection_properties['target_iqn'] not in other_iqns:
+        # Get all the targets for the current multipath device
+        current_iqns = [iqn for ip, iqn in ips_iqns]
+
+        in_use = False
+        for current in current_iqns:
+            if current in other_iqns:
+                in_use = True
+                break
+
+        # If no other multipath device attached has the same iqn
+        # as the current device
+        if not in_use:
             # disconnect if no other multipath devices with same iqn
-            self._disconnect_mpath(connection_properties)
+            self._disconnect_mpath(connection_properties, ips_iqns)
             return
 
         # else do not disconnect iscsi portals,
@@ -454,13 +487,11 @@ class ISCSIConnector(InitiatorConnector):
             return []
         return [entry for entry in devices if entry.startswith("ip-")]
 
-    def _disconnect_mpath(self, connection_properties):
-        entries = self._get_iscsi_devices()
-        ips = [ip.split("-")[1] for ip in entries
-               if connection_properties['target_iqn'] in ip]
-        for ip in ips:
+    def _disconnect_mpath(self, connection_properties, ips_iqns):
+        for ip, iqn in ips_iqns:
             props = connection_properties.copy()
             props['target_portal'] = ip
+            props['target_iqn'] = iqn
             self._disconnect_from_iscsi_portal(props)
 
         self._rescan_multipath()

diff --git a/cinder/tests/brick/test_brick_connector.py b/cinder/tests/brick/test_brick_connector.py
index cd51588d3e3d3f28c6367c5fa321487144b4bec2..d97709155193f257358f079e3d51233f6e8b65a8 100644 (file)
--- a/cinder/tests/brick/test_brick_connector.py
+++ b/cinder/tests/brick/test_brick_connector.py
@@ -181,6 +181,8 @@ class ISCSIConnectorTestCase(ConnectorTestCase):
                              ('iscsiadm -m node -T %s -p %s --op update'
                               ' -n node.startup -v automatic' % (iqn,
                               location)),
+                             ('iscsiadm -m node --rescan'),
+                             ('iscsiadm -m session --rescan'),
                              ('tee -a /sys/block/sdb/device/delete'),
                              ('iscsiadm -m node -T %s -p %s --op update'
                               ' -n node.startup -v manual' % (iqn, location)),
@@ -194,7 +196,6 @@ class ISCSIConnectorTestCase(ConnectorTestCase):
         self.assertEqual(expected_commands, self.cmds)
 
     def test_connect_volume_with_multipath(self):
-
         location = '10.0.2.15:3260'
         name = 'volume-00000001'
         iqn = 'iqn.2010-10.org.openstack:%s' % name
@@ -208,7 +209,7 @@ class ISCSIConnectorTestCase(ConnectorTestCase):
                        lambda *args, **kwargs: "%s %s" % (location, iqn))
         self.stubs.Set(self.connector_with_multipath,
                        '_get_target_portals_from_iscsiadm_output',
-                       lambda x: [location])
+                       lambda x: [[location, iqn]])
         self.stubs.Set(self.connector_with_multipath,
                        '_connect_to_iscsi_portal',
                        lambda x: None)
@@ -245,7 +246,9 @@ class ISCSIConnectorTestCase(ConnectorTestCase):
         test_output = '''10.15.84.19:3260 iqn.1992-08.com.netapp:sn.33615311
                          10.15.85.19:3260 iqn.1992-08.com.netapp:sn.33615311'''
         res = connector._get_target_portals_from_iscsiadm_output(test_output)
-        expected = ['10.15.84.19:3260', '10.15.85.19:3260']
+        ip_iqn1 = ['10.15.84.19:3260', 'iqn.1992-08.com.netapp:sn.33615311']
+        ip_iqn2 = ['10.15.85.19:3260', 'iqn.1992-08.com.netapp:sn.33615311']
+        expected = [ip_iqn1, ip_iqn2]
         self.assertEqual(expected, res)
 
     def test_get_multipath_device_name(self):
@@ -283,12 +286,16 @@ class ISCSIConnectorTestCase(ConnectorTestCase):
     def test_disconnect_volume_multipath_iscsi(self):
         result = []
 
-        def fake_disconnect_mpath(properties):
+        def fake_disconnect_from_iscsi_portal(properties):
             result.append(properties)
         iqn1 = 'iqn.2013-01.ro.com.netapp:node.netapp01'
         iqn2 = 'iqn.2013-01.ro.com.netapp:node.netapp02'
         iqns = [iqn1, iqn2]
-        dev = ('ip-10.0.0.1:3260-iscsi-%s-lun-0' % iqn1)
+        portal = '10.0.0.1:3260'
+        dev = ('ip-%s-iscsi-%s-lun-0' % (portal, iqn1))
+        self.stubs.Set(self.connector,
+                       '_get_target_portals_from_iscsiadm_output',
+                       lambda x: [[portal, iqn1]])
         self.stubs.Set(self.connector, '_rescan_iscsi', lambda: None)
         self.stubs.Set(self.connector, '_rescan_multipath', lambda: None)
         self.stubs.Set(self.connector.driver, 'get_all_block_devices',
@@ -297,27 +304,37 @@ class ISCSIConnectorTestCase(ConnectorTestCase):
                        lambda x: '/dev/mapper/md-3')
         self.stubs.Set(self.connector, '_get_multipath_iqn',
                        lambda x: iqns.pop())
-        self.stubs.Set(self.connector, '_disconnect_mpath',
-                       fake_disconnect_mpath)
-        fake_property = {'target_iqn': "You'll-never-find-this-iqn"}
+        self.stubs.Set(self.connector, '_disconnect_from_iscsi_portal',
+                       fake_disconnect_from_iscsi_portal)
+        fake_property = {'target_portal': portal,
+                         'target_iqn': iqn1}
         self.connector._disconnect_volume_multipath_iscsi(fake_property,
                                                           'fake/multipath')
-        self.assertEqual([fake_property], result)
+        # Target in use by other mp devices, don't disconnect
+        self.assertEqual([], result)
 
     def test_disconnect_volume_multipath_iscsi_without_other_mp_devices(self):
         result = []
 
-        def fake_disconnect_mpath(properties):
+        def fake_disconnect_from_iscsi_portal(properties):
             result.append(properties)
+        portal = '10.0.2.15:3260'
+        name = 'volume-00000001'
+        iqn = 'iqn.2010-10.org.openstack:%s' % name
+        self.stubs.Set(self.connector,
+                       '_get_target_portals_from_iscsiadm_output',
+                       lambda x: [[portal, iqn]])
         self.stubs.Set(self.connector, '_rescan_iscsi', lambda: None)
         self.stubs.Set(self.connector, '_rescan_multipath', lambda: None)
         self.stubs.Set(self.connector.driver, 'get_all_block_devices',
                        lambda: [])
-        self.stubs.Set(self.connector, '_disconnect_mpath',
-                       fake_disconnect_mpath)
-        fake_property = {'target_iqn': "You'll-never-find-this-iqn"}
+        self.stubs.Set(self.connector, '_disconnect_from_iscsi_portal',
+                       fake_disconnect_from_iscsi_portal)
+        fake_property = {'target_portal': portal,
+                         'target_iqn': iqn}
         self.connector._disconnect_volume_multipath_iscsi(fake_property,
                                                           'fake/multipath')
+        # Target not in use by other mp devices, disconnect
         self.assertEqual([fake_property], result)