[release-4.21] Fix IPA boot during out-of-band service steps

ironic/conductor/servicing.py

@@ -106,6 +106,9 @@ def do_node_service(task, service_steps=None, disable_ramdisk=False):
     else:
         LOG.debug('Will proceed with servicing node %(node)s '
                   'without booting the ramdisk.', {'node': node.uuid})
+        disable_ramdisk = True
+        node.set_driver_internal_info('service_disable_ramdisk', True)
+        node.save()
 
     do_next_service_step(task, step_index, disable_ramdisk=disable_ramdisk)
 

ironic/tests/unit/conductor/test_servicing.py

@@ -199,6 +199,11 @@ def test__do_node_service_out_of_band(self, mock_prep,
         self.assertEqual(tgt_prov_state, node.target_provision_state)
         mock_prep.assert_not_called()
         mock_validate.assert_called_once_with(mock.ANY, mock.ANY)
+        self.assertTrue(
+            node.driver_internal_info.get('service_disable_ramdisk'),
+            'service_disable_ramdisk must be True when no step requires '
+            'the ramdisk, so that mid-step reboots do not boot IPA'
+        )
 
     @mock.patch('ironic.drivers.modules.network.flat.FlatNetwork.validate',
                 autospec=True)
@@ -227,6 +232,11 @@ def test__do_node_service_requires_ramdisk_fallback(self, mock_prep,
         self.assertEqual(tgt_prov_state, node.target_provision_state)
         mock_prep.assert_called_once_with(mock.ANY, mock.ANY)
         mock_validate.assert_called_once_with(mock.ANY, mock.ANY)
+        self.assertFalse(
+            node.driver_internal_info.get('service_disable_ramdisk'),
+            'service_disable_ramdisk must not be True when a step requires '
+            'the ramdisk'
+        )
 
     @mock.patch('ironic.drivers.modules.network.flat.FlatNetwork.validate',
                 autospec=True)
@@ -354,13 +364,19 @@ def set_steps(task, disable_ramdisk=None):
             else:
                 mock_network_valid.assert_called_once_with(mock.ANY, task)
 
+            effective_disable = disable_ramdisk or not any(
+                s.get('requires_ramdisk') for s in service_steps)
             mock_next_step.assert_called_once_with(
-                task, 0, disable_ramdisk=disable_ramdisk)
+                task, 0, disable_ramdisk=effective_disable)
             mock_steps.assert_called_once_with(
                 task, disable_ramdisk=disable_ramdisk)
             if service_steps:
                 self.assertEqual(service_steps,
                                  node.driver_internal_info['service_steps'])
+            self.assertEqual(
+                effective_disable,
+                node.driver_internal_info.get('service_disable_ramdisk',
+                                              False))
             self.assertFalse(node.maintenance)
             self.assertNotIn('agent_secret_token', node.driver_internal_info)
 

releasenotes/notes/fix-ipa-boot-oob-service-steps-b2e4f1a9c3d70845.yaml

@@ -0,0 +1,11 @@
+---
+fixes:
+  - |
+    Fixed an unnecessary IPA boot during out-of-band service steps. When all
+    service steps declare ``requires_ramdisk=False``, the conductor correctly
+    skips the initial ramdisk boot, but ``service_disable_ramdisk`` in
+    ``driver_internal_info`` was left as ``False``. Steps that call
+    ``reboot_to_finish_step()`` internally (e.g. Redfish BIOS
+    ``apply_configuration``) would then boot IPA before the reboot, adding a
+    disruptive and unnecessary boot cycle. The flag is now set to ``True``
+    whenever all service steps are out-of-band.