Allow setting Pure host personality

Add a new configuration option for setting the Pure host personality.
It determines how the Purity system tunes the protocol used between
the array and the initiator. To ensure the array works optimally with
the host, set the personality to the name of the host operating or
virtual memory system. Valid values are aix, esxi, hitachi-vsp, hpux,
oracle-vm-server, solaris, and vms. If your system is not listed as
one of the valid host personalities, do not set the option. By
default, the host personality is not set.

Change-Id: I5065ccbed27c5b7c3b32ae8eda221c151a8bbaa9

cinder/tests/unit/volume/drivers/test_pure.py

@@ -3229,6 +3229,7 @@ class PureISCSIDriverTestCase(PureBaseSharedDriverTestCase):
         mock_generate.assert_called_with(HOSTNAME)
         self.array.create_host.assert_called_with(PURE_HOST_NAME,
                                                   iqnlist=[INITIATOR_IQN])
+        self.assertFalse(self.array.set_host.called)
         self.assertEqual(result, real_result)
 
         mock_generate.reset_mock()
@@ -3250,6 +3251,25 @@ class PureISCSIDriverTestCase(PureBaseSharedDriverTestCase):
                                                host_user=chap_user,
                                                host_password=chap_password)
 
+        self.array.reset_mock()
+        self.mock_config.use_chap_auth = False
+        self.mock_config.safe_get.return_value = 'oracle-vm-server'
+
+        # Branch where we fail due to invalid version for setting personality
+        self.assertRaises(exception.PureDriverException, self.driver._connect,
+                          self.array, vol_name, ISCSI_CONNECTOR, None, None)
+        self.assertFalse(self.array.create_host.called)
+        self.assertFalse(self.array.set_host.called)
+
+        self.array.get_rest_version.return_value = '1.14'
+
+        # Branch where personality is set
+        self.driver._connect(self.array, vol_name, ISCSI_CONNECTOR,
+                             None, None)
+        self.assertDictEqual(result, real_result)
+        self.array.set_host.assert_called_with(PURE_HOST_NAME,
+                                               personality='oracle-vm-server')
+
     @mock.patch(ISCSI_DRIVER_OBJ + "._get_host", autospec=True)
     def test_connect_already_connected(self, mock_host):
         vol, vol_name = self.new_fake_vol()

cinder/volume/drivers/pure.py

@@ -60,6 +60,11 @@ PURE_OPTS = [
                      "on the current total data reduction values. If used "
                      "this calculated value will override the "
                      "max_over_subscription_ratio config option."),
+    cfg.StrOpt("pure_host_personality",
+               choices=['aix', 'esxi', 'hitachi-vsp', 'hpux',
+                        'oracle-vm-server', 'solaris', 'vms'],
+               help="Determines how the Purity system tunes the protocol used "
+                    "between the array and the initiator."),
     # These are used as default settings.  In future these can be overridden
     # by settings in volume-type.
     cfg.IntOpt("pure_replica_interval_default", default=3600,
@@ -123,6 +128,7 @@ ASYNC_REPLICATION_REQUIRED_API_VERSIONS = [
     '1.3', '1.4', '1.5'] + SYNC_REPLICATION_REQUIRED_API_VERSIONS
 MANAGE_SNAP_REQUIRED_API_VERSIONS = [
     '1.4', '1.5'] + SYNC_REPLICATION_REQUIRED_API_VERSIONS
+PERSONALITY_REQUIRED_API_VERSIONS = ['1.14']
 
 REPL_SETTINGS_PROPAGATE_RETRY_INTERVAL = 5  # 5 seconds
 REPL_SETTINGS_PROPAGATE_MAX_RETRIES = 36  # 36 * 5 = 180 seconds
@@ -2468,6 +2474,21 @@ class PureISCSIDriver(PureBaseVolumeDriver, san.SanISCSIDriver):
                         reason=_("Unable to re-use host with unknown CHAP "
                                  "credentials configured."))
         else:
+            personality = self.configuration.safe_get('pure_host_personality')
+            if personality:
+                api_version = array.get_rest_version()
+                if api_version not in PERSONALITY_REQUIRED_API_VERSIONS:
+                    # Continuing here would mean creating a host not according
+                    # to specificiations, possibly leading to unexpected
+                    # behavior later on.
+                    msg = _('Unable to set host personality with Purity REST '
+                            'API version %(api_version)s, requires '
+                            '%(required_versions)s.') % {
+                        'api_version': api_version,
+                        'required_versions': PERSONALITY_REQUIRED_API_VERSIONS
+                    }
+                    raise exception.PureDriverException(reason=msg)
+
             host_name = self._generate_purity_host_name(connector["host"])
             LOG.info("Creating host object %(host_name)r with IQN:"
                      " %(iqn)s.", {"host_name": host_name, "iqn": iqn})
@@ -2482,6 +2503,18 @@ class PureISCSIDriver(PureBaseVolumeDriver, san.SanISCSIDriver):
                     LOG.debug('Unable to create host: %s', err.text)
                     raise exception.PureRetryableException()
 
+            if personality:
+                try:
+                    array.set_host(host_name, personality=personality)
+                except purestorage.PureHTTPError as err:
+                    if (err.code == 400 and
+                            ERR_MSG_HOST_NOT_EXIST in err.text):
+                        # If the host disappeared out from under us that's
+                        # ok, we will just retry and snag a new host.
+                        LOG.debug('Unable to set host personality: %s',
+                                  err.text)
+                        raise exception.PureRetryableException()
+
             if self.configuration.use_chap_auth:
                 try:
                     array.set_host(host_name,

doc/source/configuration/block-storage/drivers/pure-storage-driver.rst

@@ -176,6 +176,28 @@ By default, auto-eradication is disabled and all deleted volumes, snapshots,
 and consistency groups are retained on the Pure Storage array in a recoverable
 state for 24 hours from time of deletion.
 
+Setting host personality
+~~~~~~~~~~~~~~~~~~~~~~~~
+
+The host personality determines how the Purity system tunes the protocol used
+between the array and the initiator. To ensure the array works optimally with
+the host, set the personality to the name of the host operating or virtual
+memory system. Valid values are aix, esxi, hitachi-vsp, hpux, oracle-vm-server,
+solaris, and vms. If your system is not listed as one of the valid host
+personalities, do not set the option. By default, the host personality is not
+set.
+
+To set the host personality, modify the following option in the ``cinder.conf``
+file:
+
+.. code-block:: ini
+
+   pure_host_personality = <personality>
+
+.. note::
+   ``pure_host_personality`` is available from Purity REST API version 1.14,
+   and affects only newly-created hosts.
+
 SSL certification
 ~~~~~~~~~~~~~~~~~
 

releasenotes/notes/pure-host-personality-3512f7ccd961d4ad.yaml

@@ -0,0 +1,6 @@
+---
+features:
+  - |
+    Pure Storage FlashArray driver has added configuration option
+    ``pure_host_personality`` for setting the host personality upon host
+    creation (existing hosts are not affected).