From 8aa6d328f57b8981397751465d9d3d415a1d327a Mon Sep 17 00:00:00 2001
From: odonos12 <simon.odonovan@dell.com>
Date: Wed, 4 Mar 2020 12:40:55 +0000
Subject: [PATCH] PowerMax Driver - Replication array serial check

Add a check during common.py __init__ to compare
serial numbers of local and remote replication arrays
to prevent the user from defining the same array
for both R1 and R2 sides.

Change-Id: I83a712c739c315422e157f91cad1b87c01fb9cbc
---
 .../dell_emc/powermax/test_powermax_common.py | 21 +++++++++++++++++++
 .../drivers/dell_emc/powermax/common.py       | 15 ++++++++++---
 2 files changed, 33 insertions(+), 3 deletions(-)

diff --git a/cinder/tests/unit/volume/drivers/dell_emc/powermax/test_powermax_common.py b/cinder/tests/unit/volume/drivers/dell_emc/powermax/test_powermax_common.py
index 563bdc0a6f2..08ff90f82ac 100644
--- a/cinder/tests/unit/volume/drivers/dell_emc/powermax/test_powermax_common.py
+++ b/cinder/tests/unit/volume/drivers/dell_emc/powermax/test_powermax_common.py
@@ -84,6 +84,27 @@ class PowerMaxCommonTest(test.TestCase):
         self.assertTrue(self.common.next_gen)
         self.assertEqual(self.common.ucode_level, self.data.next_gen_ucode)
 
+    @mock.patch.object(rest.PowerMaxRest, 'get_array_ucode_version',
+                       return_value=tpd.PowerMaxData.next_gen_ucode)
+    @mock.patch.object(rest.PowerMaxRest, 'get_array_model_info',
+                       return_value=('PowerMax 2000', True))
+    @mock.patch.object(rest.PowerMaxRest, 'set_rest_credentials')
+    @mock.patch.object(
+        common.PowerMaxCommon, 'get_attributes_from_cinder_config',
+        return_value={'SerialNumber': tpd.PowerMaxData.array})
+    @mock.patch.object(
+        common.PowerMaxCommon, '_get_attributes_from_config')
+    def test_gather_info_rep_enabled_duplicate_serial_numbers(
+            self, mck_get_cnf, mck_get_c_cnf, mck_set, mck_model, mck_ucode):
+        is_enabled = self.common.replication_enabled
+        targets = self.common.replication_targets
+        self.common.replication_enabled = True
+        self.common.replication_targets = [self.data.array]
+        self.assertRaises(
+            exception.InvalidConfigurationValue, self.common._gather_info)
+        self.common.replication_enabled = is_enabled
+        self.common.replication_targets = targets
+
     @mock.patch.object(common.PowerMaxCommon,
                        '_gather_info')
     def test_get_attributes_from_config_short_host_template(
diff --git a/cinder/volume/drivers/dell_emc/powermax/common.py b/cinder/volume/drivers/dell_emc/powermax/common.py
index 4326c18c348..ae2eea00ad7 100644
--- a/cinder/volume/drivers/dell_emc/powermax/common.py
+++ b/cinder/volume/drivers/dell_emc/powermax/common.py
@@ -211,10 +211,19 @@ class PowerMaxCommon(object):
                       "longer supported.")
         self.rest.set_rest_credentials(array_info)
         if array_info:
+            serial_number = array_info['SerialNumber']
             self.array_model, self.next_gen = (
-                self.rest.get_array_model_info(array_info['SerialNumber']))
-            self.ucode_level = self.rest.get_array_ucode_version(
-                array_info['SerialNumber'])
+                self.rest.get_array_model_info(serial_number))
+            self.ucode_level = self.rest.get_array_ucode_version(serial_number)
+            if self.replication_enabled:
+                if serial_number in self.replication_targets:
+                    msg = (_("The same array serial number (%s) is defined "
+                             "for powermax_array and replication_device in "
+                             "cinder.conf. Please ensure your "
+                             "target_device_id points to a different "
+                             "array." % serial_number))
+                    LOG.error(msg)
+                    raise exception.InvalidConfigurationValue(msg)
         finalarrayinfolist = self._get_slo_workload_combinations(
             array_info)
         self.pool_info['arrays_info'] = finalarrayinfolist