If rescue fails don't error the instance

If a rescue attempt fails, the VM's state should return to what it was
before the rescue attempt started, and the user should be notified of
the failure.

Fixes bug: 1170328

Change-Id: If5e97d06a3617adad83a4bba2ac6320616bbe83b

1 files changed, 7 insertions, 2 deletions

diff --git a/nova/compute/manager.py b/nova/compute/manager.py
index 5da050f60..f1ab1629e 100755
--- a/nova/compute/manager.py
+++ b/nova/compute/manager.py
@@ -2007,7 +2007,6 @@ class ComputeManager(manager.SchedulerDependentManager):
     @exception.wrap_exception(notifier=notifier, publisher_id=publisher_id())
     @reverts_task_state
     @wrap_instance_event
-    @wrap_instance_fault
     def rescue_instance(self, context, instance, rescue_password=None):
         """
         Rescue an instance on this host.
@@ -2028,10 +2027,16 @@ class ComputeManager(manager.SchedulerDependentManager):
         else:
             rescue_image_meta = {}
 
-        with self._error_out_instance_on_exception(context, instance['uuid']):
+        try:
             self.driver.rescue(context, instance,
                                self._legacy_nw_info(network_info),
                                rescue_image_meta, admin_password)
+        except Exception as e:
+            LOG.exception(_("Error trying to Rescue Instance"),
+                          instance=instance)
+            raise exception.InstanceNotRescuable(
+                instance_id=instance['uuid'],
+                reason=_("Driver Error: %s") % unicode(e))
 
         current_power_state = self._get_power_state(context, instance)
         self._instance_update(context,