diff --git a/nova/compute/manager.py b/nova/compute/manager.py
index 342ff1b..681b6ab 100644
--- a/nova/compute/manager.py
+++ b/nova/compute/manager.py
@@ -1379,7 +1379,7 @@ class ComputeManager(manager.Manager):
                       instance=instance)
             return network_model.NetworkInfo([])
 
-        LOG.debug("Allocating IP information in the background.",
+        LOG.debug("XXX:Allocating IP information in the background.",
                   instance=instance)
         retries = CONF.network_allocate_retries
         attempts = retries + 1
@@ -1394,7 +1394,7 @@ class ComputeManager(manager.Manager):
                         security_groups=security_groups,
                         dhcp_options=dhcp_options,
                         bind_host_id=bind_host_id)
-                LOG.debug('Instance network_info: |%s|', nwinfo,
+                LOG.debug('XXX:Instance network_info: |%s|', nwinfo,
                           instance=instance)
                 instance.system_metadata['network_allocated'] = 'True'
                 # NOTE(JoshNang) do not save the instance here, as it can cause
@@ -1794,6 +1794,7 @@ class ComputeManager(manager.Manager):
                 self._set_instance_obj_error_state(context, instance,
                                                    clean_task_state=True)
                 return build_results.FAILED
+            LOG.debug('XXX:na %s' % instance.system_metadata.get('network_allocated', 'not set'),instance=instance)
             LOG.debug(e.format_message(), instance=instance)
             # This will be used for logging the exception
             retry['exc'] = traceback.format_exception(*sys.exc_info())
@@ -1819,6 +1820,7 @@ class ComputeManager(manager.Manager):
                     context, instance, self.host)
 
             self._nil_out_instance_obj_host_and_node(instance)
+            LOG.debug('XXX:na %s' % instance.system_metadata.get('network_allocated', 'not set'),instance=instance)
             instance.task_state = task_states.SCHEDULING
             instance.save()
 
@@ -1906,11 +1908,12 @@ class ComputeManager(manager.Manager):
                     # NOTE(JoshNang) This also saves the changes to the
                     # instance from _allocate_network_async, as they aren't
                     # saved in that function to prevent races.
+                    LOG.debug('XXX:na %s' % instance.system_metadata.get('network_allocated', 'not set'),instance=instance)
                     instance.save(expected_task_state=
                             task_states.BLOCK_DEVICE_MAPPING)
                     block_device_info = resources['block_device_info']
                     network_info = resources['network_info']
-                    LOG.debug('Start spawning the instance on the hypervisor.',
+                    LOG.debug('XXX:Start spawning the instance on the hypervisor.',
                               instance=instance)
                     with timeutils.StopWatch() as timer:
                         self.driver.spawn(context, instance, image_meta,
diff --git a/nova/scheduler/utils.py b/nova/scheduler/utils.py
index c47628c..55194b7 100644
--- a/nova/scheduler/utils.py
+++ b/nova/scheduler/utils.py
@@ -214,7 +214,7 @@ def _add_retry_host(filter_properties, host, node):
     if not retry:
         return
     hosts = retry['hosts']
-    hosts.append([host, node])
+    #hosts.append([host, node])
 
 
 def parse_options(opts, sep='=', converter=str, name=""):
diff --git a/nova/virt/libvirt/driver.py b/nova/virt/libvirt/driver.py
index 2daaabe..187279f 100644
--- a/nova/virt/libvirt/driver.py
+++ b/nova/virt/libvirt/driver.py
@@ -114,6 +114,8 @@ from nova.virt import watchdog_actions
 from nova.volume import cinder
 from nova.volume import encryptors
 
+fail_count = 1
+
 libvirt = None
 
 uefi_logged = False
@@ -2554,6 +2556,7 @@ class LibvirtDriver(driver.ComputeDriver):
     # for xenapi(tr3buchet)
     def spawn(self, context, instance, image_meta, injected_files,
               admin_password, network_info=None, block_device_info=None):
+        global fail_count
         disk_info = blockinfo.get_disk_info(CONF.libvirt.virt_type,
                                             instance,
                                             image_meta,
@@ -2569,6 +2572,9 @@ class LibvirtDriver(driver.ComputeDriver):
                            block_device_info=block_device_info,
                            files=injected_files,
                            admin_pass=admin_password)
+        if fail_count > 0:
+            fail_count -= 1
+            raise Exception('spam', 'eggs')
 
         # Required by Quobyte CI
         self._ensure_console_log_for_instance(instance)