diff --git a/os_brick/initiator/connectors/scaleio.py b/os_brick/initiator/connectors/scaleio.py
index 9d798eb6d..30215fbfc 100644
--- a/os_brick/initiator/connectors/scaleio.py
+++ b/os_brick/initiator/connectors/scaleio.py
@@ -66,6 +66,17 @@ class ScaleIOConnector(base.BaseLinuxConnector):
         self.iops_limit = None
         self.bandwidth_limit = None
 
+    def _get_password_token(self, connection_properties):
+        # In old connection format we had the password and token in properties
+        if 'serverPassword' in connection_properties:
+            return (connection_properties['serverPassword'],
+                    connection_properties['serverToken'])
+
+        # The new format reads password from file and doesn't have the token
+        password = self._get_connector_password(
+            connection_properties['config_group'])
+        return password, None
+
     @staticmethod
     def get_connector_properties(root_helper, *args, **kwargs):
         """The ScaleIO connector properties."""
@@ -299,9 +310,8 @@ class ScaleIOConnector(base.BaseLinuxConnector):
         self.server_ip = connection_properties['serverIP']
         self.server_port = connection_properties['serverPort']
         self.server_username = connection_properties['serverUsername']
-        self.server_password = self._get_connector_password(
-            connection_properties['config_group'],
-        )
+        self.server_password, self.server_token = self._get_password_token(
+            connection_properties)
         self.iops_limit = connection_properties['iopsLimit']
         self.bandwidth_limit = connection_properties['bandwidthLimit']
         device_info = {'type': 'block',
diff --git a/os_brick/tests/initiator/connectors/test_scaleio.py b/os_brick/tests/initiator/connectors/test_scaleio.py
index 45f807b8d..8f6b31746 100644
--- a/os_brick/tests/initiator/connectors/test_scaleio.py
+++ b/os_brick/tests/initiator/connectors/test_scaleio.py
@@ -175,6 +175,24 @@ class ScaleIOConnectorTestCase(test_connector.ConnectorTestCase):
         self.connector.connect_volume(self.fake_connection_properties)
         self.get_password_mock.assert_called_once()
 
+    def test_connect_volume_old_connection_properties(self):
+        """Successful connect to volume"""
+        connection_properties = {
+            'hostIP': test_connector.MY_IP,
+            'serverIP': test_connector.MY_IP,
+            'scaleIO_volname': self.vol['name'],
+            'scaleIO_volume_id': self.vol['provider_id'],
+            'serverPort': 443,
+            'serverUsername': 'test',
+            'serverPassword': 'fake',
+            'serverToken': 'fake_token',
+            'iopsLimit': None,
+            'bandwidthLimit': None
+        }
+
+        self.connector.connect_volume(connection_properties)
+        self.get_password_mock.assert_not_called()
+
     def test_connect_with_bandwidth_limit(self):
         """Successful connect to volume with bandwidth limit"""
         self.fake_connection_properties['bandwidthLimit'] = '500'
diff --git a/releasenotes/notes/bug-1823200-scaleio-upgrade-3e83b5c9dd148714.yaml b/releasenotes/notes/bug-1823200-scaleio-upgrade-3e83b5c9dd148714.yaml
new file mode 100644
index 000000000..ccce93f89
--- /dev/null
+++ b/releasenotes/notes/bug-1823200-scaleio-upgrade-3e83b5c9dd148714.yaml
@@ -0,0 +1,10 @@
+---
+fixes:
+  - |
+    `Bug #1823200 <https://bugs.launchpad.net/cinder/+bug/1823200>`_:
+    Prior fixes for this bug changed the connection properties but did
+    not take into account an upgrade scenario in which currently attached
+    volumes had the old format connection properties and could fail on
+    detatch with "KeyError: 'config_group'".  This release updates the
+    'scaleio' connector to handle this situation.  It is only applicable
+    to deployments using a Dell EMC PowerFlex/VxFlex OS/ScaleIO backend.