diff --git a/os_brick/initiator/connectors/storpool.py b/os_brick/initiator/connectors/storpool.py
index 3e5a2da17..d5e5601df 100644
--- a/os_brick/initiator/connectors/storpool.py
+++ b/os_brick/initiator/connectors/storpool.py
@@ -16,6 +16,8 @@
 from __future__ import absolute_import
 
 import os
+import time
+
 import six
 
 from oslo_log import log as logging
@@ -212,11 +214,27 @@ class StorPoolConnector(base.BaseLinuxConnector):
         # should have picked up the change already, so it is enough to query
         # the actual disk device to see if its size is correct.
         #
-        # TODO(pp): query the API to see if this is really the case
         volume_id = connection_properties.get('volume', None)
         if volume_id is None:
             raise exception.BrickException(
                 'Invalid StorPool connection data, no volume ID specified.')
+
+        # Get the expected (new) size from the StorPool API
         volume = self._attach.volumeName(volume_id)
+        LOG.debug('Querying the StorPool API for the size of %(vol)s',
+                  {'vol': volume})
+        vdata = self._attach.api().volumeList(volume)[0]
+        LOG.debug('Got size %(size)d', {'size': vdata.size})
+
+        # Wait for the StorPool client to update the size of the local device
         path = '/dev/storpool/' + volume
-        return self._get_device_size(path)
+        for _ in range(10):
+            size = self._get_device_size(path)
+            LOG.debug('Got local size %(size)d', {'size': size})
+            if size == vdata.size:
+                return size
+            time.sleep(0.1)
+        else:
+            size = self._get_device_size(path)
+            LOG.debug('Last attempt: local size %(size)d', {'size': size})
+            return size
diff --git a/os_brick/tests/initiator/connectors/test_storpool.py b/os_brick/tests/initiator/connectors/test_storpool.py
index 733409c38..76230b5ea 100644
--- a/os_brick/tests/initiator/connectors/test_storpool.py
+++ b/os_brick/tests/initiator/connectors/test_storpool.py
@@ -79,13 +79,16 @@ class StorPoolConnectorTestCase(test_connector.ConnectorTestCase):
     def volumeName(self, vid):
         return volumeNameExt(vid)
 
+    def get_fake_size(self):
+        return self.fakeSize
+
     def execute(self, *cmd, **kwargs):
         if cmd[0] == 'blockdev':
             self.assertEqual(len(cmd), 3)
             self.assertEqual(cmd[1], '--getsize64')
             self.assertEqual(cmd[2], '/dev/storpool/' +
                              self.volumeName(self.fakeProp['volume']))
-            return (str(self.fakeSize) + '\n', None)
+            return (str(self.get_fake_size()) + '\n', None)
         raise Exception("Unrecognized command passed to " +
                         type(self).__name__ + ".execute(): " +
                         str.join(", ", map(lambda s: "'" + s + "'", cmd)))
@@ -148,5 +151,42 @@ class StorPoolConnectorTestCase(test_connector.ConnectorTestCase):
             self.test_connect_volume()
 
         self.fakeSize += 1024 * 1024 * 1024
-        newSize = self.connector.extend_volume(self.fakeProp)
+
+        size_list = [self.fakeSize, self.fakeSize - 1, self.fakeSize - 2]
+
+        vdata = mock.MagicMock(spec=['size'])
+        vdata.size = self.fakeSize
+        vdata_list = [[vdata]]
+
+        def fake_volume_list(name):
+            self.assertEqual(
+                name,
+                self.adb.volumeName(self.fakeProp['volume'])
+            )
+            return vdata_list.pop()
+
+        api = mock.MagicMock(spec=['volumeList'])
+        api.volumeList = mock.MagicMock(spec=['__call__'])
+
+        with mock.patch.object(
+            self.adb, attribute='api', spec=['__call__']
+        ) as fake_api, mock.patch.object(
+            self, attribute='get_fake_size', spec=['__call__']
+        ) as fake_size, mock.patch('time.sleep') as fake_sleep:
+            fake_api.return_value = api
+            api.volumeList.side_effect = fake_volume_list
+
+            fake_size.side_effect = size_list.pop
+
+            newSize = self.connector.extend_volume(self.fakeProp)
+
+            self.assertEqual(fake_api.call_count, 1)
+            self.assertEqual(api.volumeList.call_count, 1)
+            self.assertListEqual(vdata_list, [])
+
+            self.assertEqual(fake_size.call_count, 3)
+            self.assertListEqual(size_list, [])
+
+            self.assertEqual(fake_sleep.call_count, 2)
+
         self.assertEqual(newSize, self.fakeSize)