3PAR: Fix terminate_connection when failed over

Terminate connection will fail when a detach is called on a failed
over volume. This patch allows terminate_connection to succeed in
order to allow reattachments to secondary arrays.

Closes-Bug: #1580691
Change-Id: Ibf91882b94ea5cca51dc7be91ec05179391a9b78

cinder/tests/unit/fake_hpe_client_exceptions.py

@@ -73,7 +73,7 @@ class ClientException(Exception):
         return formatted_string
 
 
-class HTTPConflict(Exception):
+class HTTPConflict(ClientException):
     http_status = 409
     message = "Conflict"
 
@@ -85,7 +85,7 @@ class HTTPConflict(Exception):
         return self._error_desc
 
 
-class HTTPNotFound(Exception):
+class HTTPNotFound(ClientException):
     http_status = 404
     message = "Not found"
 
@@ -95,7 +95,7 @@ class HTTPForbidden(ClientException):
     message = "Forbidden"
 
 
-class HTTPBadRequest(Exception):
+class HTTPBadRequest(ClientException):
     http_status = 400
     message = "Bad request"
 
@@ -105,7 +105,7 @@ class HTTPUnauthorized(ClientException):
     message = "Unauthorized"
 
 
-class HTTPServerError(Exception):
+class HTTPServerError(ClientException):
     http_status = 500
     message = "Error"
 

cinder/tests/unit/test_hpe3par.py

@@ -2557,6 +2557,30 @@ class HPE3PARBaseDriver(object):
                 expected +
                 self.standard_logout)
 
+    def test_terminate_connection_from_primary_when_failed_over(self):
+        # setup_mock_client drive with default configuration
+        # and return the mock HTTP 3PAR client
+        mock_client = self.setup_driver()
+        mock_client.getHostVLUNs.side_effect = hpeexceptions.HTTPNotFound(
+            error={'desc': 'The host does not exist.'})
+
+        with mock.patch.object(hpecommon.HPE3PARCommon,
+                               '_create_client') as mock_create_client:
+            mock_create_client.return_value = mock_client
+
+            self.driver._active_backend_id = 'some_id'
+            self.driver.terminate_connection(
+                self.volume,
+                self.connector,
+                force=True)
+
+            # When the volume is still attached to the primary array after a
+            # fail-over, there should be no call to delete the VLUN(s) or the
+            # host. We can assert these methods were not called to make sure
+            # the proper exceptions are being raised.
+            self.assertEqual(0, mock_client.deleteVLUN.call_count)
+            self.assertEqual(0, mock_client.deleteHost.call_count)
+
     def test_extend_volume(self):
         # setup_mock_client drive with default configuration
         # and return the mock HTTP 3PAR client

cinder/volume/drivers/hpe/hpe_3par_common.py

@@ -241,10 +241,11 @@ class HPE3PARCommon(object):
         3.0.22 - Rework delete_vlun. Bug #1582922
         3.0.23 - Fix CG create failures with long display name or special
                  characters. bug #1573647
+        3.0.24 - Fix terminate connection on failover
 
     """
 
-    VERSION = "3.0.23"
+    VERSION = "3.0.24"
 
     stats = {}
 
@@ -2509,6 +2510,20 @@ class HPE3PARCommon(object):
             return
         except hpeexceptions.HTTPNotFound as e:
             if 'host does not exist' in e.get_description():
+                # If a host is failed-over, we want to allow the detach to
+                # 'succeed' when it cannot find the host. We can simply
+                # return out of the terminate connection in order for things
+                # to be updated correctly.
+                if self._active_backend_id:
+                    LOG.warning(_LW("Because the host is currently in a "
+                                    "failed-over state, the volume will not "
+                                    "be properly detached from the primary "
+                                    "array. The detach will be considered a "
+                                    "success as far as Cinder is concerned. "
+                                    "The volume can now be attached to the "
+                                    "secondary target."))
+                    return
+                else:
                     # use the wwn to see if we can find the hostname
                     hostname = self._get_3par_hostname_from_wwn_iqn(wwn, iqn)
                     # no 3par host, re-throw