Fix iLO drivers inconsistent boot mode default value

When no boot mode is explicitly passed to iLO drivers, it picks
default boot mode based on series of factors like, pending boot
mode setting, UEFI boot mode support on the node. This causes
confusion to the users as these factors are node specific and
beyond user's control. User expects a predictable behavior when
no boot mode is explicitly passed.
A new configuration parameter '[ilo]/default_boot_mode' has
been added to specify default boot mode. It would be used if no
boot mode is explicitly passed to iLO drivers.

Change-Id: I4efd28985674bedabe42fe786135255698425321
Closes-Bug: #1604002

doc/source/drivers/ilo.rst

@@ -626,6 +626,11 @@ mode (Legacy BIOS or UEFI).
 
 * When boot mode capability is not configured:
 
+  - If config variable ``default_boot_mode`` in ``[ilo]`` section of
+    ironic configuration file is set to either 'bios' or 'uefi', then iLO
+    drivers use that boot mode for provisioning the baremetal ProLiant
+    servers.
+
   - If the pending boot mode is set on the node then iLO drivers use that boot
     mode for provisioning the baremetal ProLiant servers.
 

etc/ironic/ironic.conf.sample

@@ -1331,6 +1331,15 @@
 # CA certificate file to validate iLO. (string value)
 #ca_file = <None>
 
+# Default boot mode to be used in provisioning when
+# "boot_mode" capability is not provided in
+# the"properties/capabilities" of the node. The default is
+# "auto" for backward compatibility. When "auto" is specified,
+# default boot mode will be selected based on boot mode
+# settings on the system. (string value)
+# Allowed values: auto, bios, uefi
+#default_boot_mode = auto
+
 
 [inspector]
 

ironic/conf/ilo.py

@@ -80,6 +80,15 @@ opts = [
                       'operations')),
     cfg.StrOpt('ca_file',
                help=_('CA certificate file to validate iLO.')),
+    cfg.StrOpt('default_boot_mode',
+               default='auto',
+               choices=['auto', 'bios', 'uefi'],
+               help=_('Default boot mode to be used in provisioning when '
+                      '"boot_mode" capability is not provided in the'
+                      '"properties/capabilities" of the node. The default is '
+                      '"auto" for backward compatibility. When "auto" is '
+                      'specified, default boot mode will be selected based '
+                      'on boot mode settings on the system.')),
 ]
 
 

ironic/drivers/modules/ilo/common.py

@@ -437,12 +437,22 @@ def update_boot_mode(task):
     node = task.node
     boot_mode = deploy_utils.get_boot_mode_for_deploy(node)
 
-    if boot_mode is not None:
+    # No boot mode found. Check if default_boot_mode is defined
+    if not boot_mode and (CONF.ilo.default_boot_mode in ['bios', 'uefi']):
+        boot_mode = CONF.ilo.default_boot_mode
+        instance_info = node.instance_info
+        instance_info['deploy_boot_mode'] = boot_mode
+        node.instance_info = instance_info
+        node.save()
+
+    # Boot mode is computed, setting it for the deploy
+    if boot_mode:
         LOG.debug("Node %(uuid)s boot mode is being set to %(boot_mode)s",
                   {'uuid': node.uuid, 'boot_mode': boot_mode})
         set_boot_mode(node, boot_mode)
         return
 
+    # Computing boot mode based on boot mode settings on bare metal
     LOG.debug("Check pending boot mode for node %s.", node.uuid)
     ilo_object = get_ilo_object(node)
 

ironic/tests/unit/drivers/modules/ilo/test_common.py

@@ -373,9 +373,22 @@ class IloCommonMethodsTestCase(db_base.DbTestCase):
             ilo_common.update_boot_mode(task)
             set_boot_mode_mock.assert_called_once_with(task.node, 'bios')
 
+    @mock.patch.object(ilo_common, 'set_boot_mode', spec_set=True,
+                       autospec=True)
+    def test_update_boot_mode_use_def_boot_mode(self,
+                                                set_boot_mode_mock):
+        self.config(default_boot_mode='bios', group='ilo')
+        with task_manager.acquire(self.context, self.node.uuid,
+                                  shared=False) as task:
+            ilo_common.update_boot_mode(task)
+            set_boot_mode_mock.assert_called_once_with(task.node, 'bios')
+            self.assertEqual('bios',
+                             task.node.instance_info['deploy_boot_mode'])
+
     @mock.patch.object(ilo_common, 'get_ilo_object', spec_set=True,
                        autospec=True)
     def test_update_boot_mode(self, get_ilo_object_mock):
+        self.config(default_boot_mode="auto", group='ilo')
         ilo_mock_obj = get_ilo_object_mock.return_value
         ilo_mock_obj.get_pending_boot_mode.return_value = 'LEGACY'
 

releasenotes/notes/ilo-inconsistent-default-boot-mode-ef5a7c56372f89f1.yaml

@@ -0,0 +1,12 @@
+---
+fixes:
+  - When no boot mode is explicitly set on a node using
+    an iLO driver, ironic automatically picks a boot
+    mode based on hardware capabilities. This confuses
+    deployers, as these factors are system specific and
+    not configurable. In order to ensure predictable
+    behavior, a new configuration parameter,
+    ``[ilo]/default_boot_mode``, was added to allow
+    deployers to explicitly set a default. The default
+    value of this option keeps behavior consistent for
+    existing deployments.