Comment 2 for bug 1821798

Here is an extract from the nova compute logs, when that error occurs (RH OSP 13):

INFO nova.compute.manager [req-... ... ... - default default] [instance: ...] Retrieving diagnostics
ERROR oslo_messaging.rpc.server [req-... ... ... - default default] Exception during message handling: IndexError: list index out of range
ERROR oslo_messaging.rpc.server Traceback (most recent call last):
ERROR oslo_messaging.rpc.server File "/usr/lib/python2.7/site-packages/oslo_messaging/rpc/server.py", line 163, in _process_incoming
ERROR oslo_messaging.rpc.server res = self.dispatcher.dispatch(message)
ERROR oslo_messaging.rpc.server File "/usr/lib/python2.7/site-packages/oslo_messaging/rpc/dispatcher.py", line 220, in dispatch
ERROR oslo_messaging.rpc.server return self._do_dispatch(endpoint, method, ctxt, args)
ERROR oslo_messaging.rpc.server File "/usr/lib/python2.7/site-packages/oslo_messaging/rpc/dispatcher.py", line 190, in _do_dispatch
ERROR oslo_messaging.rpc.server result = func(ctxt, **new_args)
ERROR oslo_messaging.rpc.server File "/usr/lib/python2.7/site-packages/nova/exception_wrapper.py", line 76, in wrapped
ERROR oslo_messaging.rpc.server function_name, call_dict, binary)
ERROR oslo_messaging.rpc.server File "/usr/lib/python2.7/site-packages/oslo_utils/excutils.py", line 220, in __exit__
ERROR oslo_messaging.rpc.server self.force_reraise()
ERROR oslo_messaging.rpc.server File "/usr/lib/python2.7/site-packages/oslo_utils/excutils.py", line 196, in force_reraise
ERROR oslo_messaging.rpc.server six.reraise(self.type_, self.value, self.tb)
ERROR oslo_messaging.rpc.server File "/usr/lib/python2.7/site-packages/nova/exception_wrapper.py", line 67, in wrapped
ERROR oslo_messaging.rpc.server return f(self, context, *args, **kw)
ERROR oslo_messaging.rpc.server File "/usr/lib/python2.7/site-packages/nova/compute/manager.py", line 214, in decorated_function
ERROR oslo_messaging.rpc.server kwargs['instance'], e, sys.exc_info())
ERROR oslo_messaging.rpc.server File "/usr/lib/python2.7/site-packages/oslo_utils/excutils.py", line 220, in __exit__
ERROR oslo_messaging.rpc.server self.force_reraise()
ERROR oslo_messaging.rpc.server File "/usr/lib/python2.7/site-packages/oslo_utils/excutils.py", line 196, in force_reraise
ERROR oslo_messaging.rpc.server six.reraise(self.type_, self.value, self.tb)
ERROR oslo_messaging.rpc.server File "/usr/lib/python2.7/site-packages/nova/compute/manager.py", line 202, in decorated_function
ERROR oslo_messaging.rpc.server return function(self, context, *args, **kwargs)
ERROR oslo_messaging.rpc.server File "/usr/lib/python2.7/site-packages/nova/compute/manager.py", line 4624, in get_instance_diagnostics
ERROR oslo_messaging.rpc.server return self.driver.get_instance_diagnostics(instance)
ERROR oslo_messaging.rpc.server File "/usr/lib/python2.7/site-packages/nova/virt/libvirt/driver.py", line 8519, in get_instance_diagnostics
ERROR oslo_messaging.rpc.server diags.nic_details[index].mac_address = node.get('address')
ERROR oslo_messaging.rpc.server IndexError: list index out of range
ERROR oslo_messaging.rpc.server