yahoo-eng-team team mailing list archive

Thread
Date
[Bug 1823198] [NEW] NetworkAmbiguous traceback in nova-compute logs even though it's a user error

To: yahoo-eng-team@xxxxxxxxxxxxxxxxxxx
From: Matt Riedemann <mriedem.os@xxxxxxxxx>
Date: Thu, 04 Apr 2019 15:25:36 -0000
Reply-to: Bug 1823198 <1823198@xxxxxxxxxxxxxxxxxx>
Sender: bounces@xxxxxxxxxxxxx
Public bug reported:

There is a tempest negative test which is trying to attach a network
interface to a server but it is not requesting a specific network or
port:

http://logs.openstack.org/58/637058/15/check/nova-
next/f4e8140/logs/tempest.txt.gz#_2019-04-04_00_07_20_973

2019-04-04 00:07:20.973 7584 INFO tempest.lib.common.rest_client [req-47bc59bc-01de-450c-9185-3c0b9dc4bf51 ] Request (AttachInterfacesTestJSON:test_create_list_show_delete_interfaces_by_network_port): 400 POST https://104.130.239.125/compute/v2.1/servers/7f24a95b-b5be-4269-980b-a92f3c07c7ca/os-interface 0.678s
2019-04-04 00:07:20.974 7584 DEBUG tempest.lib.common.rest_client [req-47bc59bc-01de-450c-9185-3c0b9dc4bf51 ] Request - Headers: {'Content-Type': 'application/json', 'Accept': 'application/json', 'X-Auth-Token': '<omitted>'}
        Body: {"interfaceAttachment": {}}
    Response - Headers: {'date': 'Thu, 04 Apr 2019 00:07:20 GMT', 'server': 'Apache/2.4.29 (Ubuntu)', 'openstack-api-version': 'compute 2.1', 'x-openstack-nova-api-version': '2.1', 'vary': 'OpenStack-API-Version,X-OpenStack-Nova-API-Version', 'content-type': 'application/json; charset=UTF-8', 'content-length': '115', 'x-openstack-request-id': 'req-47bc59bc-01de-450c-9185-3c0b9dc4bf51', 'x-compute-request-id': 'req-47bc59bc-01de-450c-9185-3c0b9dc4bf51', 'connection': 'close', 'status': '400', 'content-location': 'https://104.130.239.125/compute/v2.1/servers/7f24a95b-b5be-4269-980b-a92f3c07c7ca/os-interface'}
        Body: b'{"badRequest": {"code": 400, "message": "Multiple possible networks found, use a Network ID to be more specific."}}' _log_request_full /opt/stack/new/tempest/tempest/lib/common/rest_client.py:440

Which results in a NetworkAmbiguous error response from the compute API
as seen above.

The problem is this is a synchronous call from nova-api to nova-compute
and results in an exception traceback in the nova-compute logs:

logs.openstack.org/58/637058/15/check/nova-
next/f4e8140/logs/screen-n-cpu.txt.gz?level=TRACE#_Apr_04_00_07_20_968719

Apr 04 00:07:20.968719 ubuntu-bionic-rax-iad-0004701322 nova-compute[32008]: ERROR oslo_messaging.rpc.server [None req-47bc59bc-01de-450c-9185-3c0b9dc4bf51 tempest-AttachInterfacesTestJSON-791222649 tempest-AttachInterfacesTestJSON-791222649] Exception during message handling: nova.exception.NetworkAmbiguous: Multiple possible networks found, use a Network ID to be more specific.
Apr 04 00:07:20.968719 ubuntu-bionic-rax-iad-0004701322 nova-compute[32008]: ERROR oslo_messaging.rpc.server Traceback (most recent call last):
Apr 04 00:07:20.968719 ubuntu-bionic-rax-iad-0004701322 nova-compute[32008]: ERROR oslo_messaging.rpc.server   File "/usr/local/lib/python3.6/dist-packages/oslo_messaging/rpc/server.py", line 166, in _process_incoming
Apr 04 00:07:20.968719 ubuntu-bionic-rax-iad-0004701322 nova-compute[32008]: ERROR oslo_messaging.rpc.server     res = self.dispatcher.dispatch(message)
Apr 04 00:07:20.968719 ubuntu-bionic-rax-iad-0004701322 nova-compute[32008]: ERROR oslo_messaging.rpc.server   File "/usr/local/lib/python3.6/dist-packages/oslo_messaging/rpc/dispatcher.py", line 265, in dispatch
Apr 04 00:07:20.968719 ubuntu-bionic-rax-iad-0004701322 nova-compute[32008]: ERROR oslo_messaging.rpc.server     return self._do_dispatch(endpoint, method, ctxt, args)
Apr 04 00:07:20.968719 ubuntu-bionic-rax-iad-0004701322 nova-compute[32008]: ERROR oslo_messaging.rpc.server   File "/usr/local/lib/python3.6/dist-packages/oslo_messaging/rpc/dispatcher.py", line 194, in _do_dispatch
Apr 04 00:07:20.968719 ubuntu-bionic-rax-iad-0004701322 nova-compute[32008]: ERROR oslo_messaging.rpc.server     result = func(ctxt, **new_args)
Apr 04 00:07:20.968719 ubuntu-bionic-rax-iad-0004701322 nova-compute[32008]: ERROR oslo_messaging.rpc.server   File "/opt/stack/new/nova/nova/exception_wrapper.py", line 79, in wrapped
Apr 04 00:07:20.968719 ubuntu-bionic-rax-iad-0004701322 nova-compute[32008]: ERROR oslo_messaging.rpc.server     function_name, call_dict, binary, tb)
Apr 04 00:07:20.968719 ubuntu-bionic-rax-iad-0004701322 nova-compute[32008]: ERROR oslo_messaging.rpc.server   File "/usr/local/lib/python3.6/dist-packages/oslo_utils/excutils.py", line 220, in __exit__
Apr 04 00:07:20.968719 ubuntu-bionic-rax-iad-0004701322 nova-compute[32008]: ERROR oslo_messaging.rpc.server     self.force_reraise()
Apr 04 00:07:20.968719 ubuntu-bionic-rax-iad-0004701322 nova-compute[32008]: ERROR oslo_messaging.rpc.server   File "/usr/local/lib/python3.6/dist-packages/oslo_utils/excutils.py", line 196, in force_reraise
Apr 04 00:07:20.968719 ubuntu-bionic-rax-iad-0004701322 nova-compute[32008]: ERROR oslo_messaging.rpc.server     six.reraise(self.type_, self.value, self.tb)
Apr 04 00:07:20.968719 ubuntu-bionic-rax-iad-0004701322 nova-compute[32008]: ERROR oslo_messaging.rpc.server   File "/usr/local/lib/python3.6/dist-packages/six.py", line 693, in reraise
Apr 04 00:07:20.968719 ubuntu-bionic-rax-iad-0004701322 nova-compute[32008]: ERROR oslo_messaging.rpc.server     raise value
Apr 04 00:07:20.968719 ubuntu-bionic-rax-iad-0004701322 nova-compute[32008]: ERROR oslo_messaging.rpc.server   File "/opt/stack/new/nova/nova/exception_wrapper.py", line 69, in wrapped
Apr 04 00:07:20.968719 ubuntu-bionic-rax-iad-0004701322 nova-compute[32008]: ERROR oslo_messaging.rpc.server     return f(self, context, *args, **kw)
Apr 04 00:07:20.968719 ubuntu-bionic-rax-iad-0004701322 nova-compute[32008]: ERROR oslo_messaging.rpc.server   File "/opt/stack/new/nova/nova/compute/utils.py", line 1349, in decorated_function
Apr 04 00:07:20.968719 ubuntu-bionic-rax-iad-0004701322 nova-compute[32008]: ERROR oslo_messaging.rpc.server     return function(self, context, *args, **kwargs)
Apr 04 00:07:20.968719 ubuntu-bionic-rax-iad-0004701322 nova-compute[32008]: ERROR oslo_messaging.rpc.server   File "/opt/stack/new/nova/nova/compute/manager.py", line 213, in decorated_function
Apr 04 00:07:20.968719 ubuntu-bionic-rax-iad-0004701322 nova-compute[32008]: ERROR oslo_messaging.rpc.server     kwargs['instance'], e, sys.exc_info())
Apr 04 00:07:20.968719 ubuntu-bionic-rax-iad-0004701322 nova-compute[32008]: ERROR oslo_messaging.rpc.server   File "/usr/local/lib/python3.6/dist-packages/oslo_utils/excutils.py", line 220, in __exit__
Apr 04 00:07:20.968719 ubuntu-bionic-rax-iad-0004701322 nova-compute[32008]: ERROR oslo_messaging.rpc.server     self.force_reraise()
Apr 04 00:07:20.968719 ubuntu-bionic-rax-iad-0004701322 nova-compute[32008]: ERROR oslo_messaging.rpc.server   File "/usr/local/lib/python3.6/dist-packages/oslo_utils/excutils.py", line 196, in force_reraise
Apr 04 00:07:20.968719 ubuntu-bionic-rax-iad-0004701322 nova-compute[32008]: ERROR oslo_messaging.rpc.server     six.reraise(self.type_, self.value, self.tb)
Apr 04 00:07:20.968719 ubuntu-bionic-rax-iad-0004701322 nova-compute[32008]: ERROR oslo_messaging.rpc.server   File "/usr/local/lib/python3.6/dist-packages/six.py", line 693, in reraise
Apr 04 00:07:20.968719 ubuntu-bionic-rax-iad-0004701322 nova-compute[32008]: ERROR oslo_messaging.rpc.server     raise value
Apr 04 00:07:20.968719 ubuntu-bionic-rax-iad-0004701322 nova-compute[32008]: ERROR oslo_messaging.rpc.server   File "/opt/stack/new/nova/nova/compute/manager.py", line 201, in decorated_function
Apr 04 00:07:20.968719 ubuntu-bionic-rax-iad-0004701322 nova-compute[32008]: ERROR oslo_messaging.rpc.server     return function(self, context, *args, **kwargs)
Apr 04 00:07:20.968719 ubuntu-bionic-rax-iad-0004701322 nova-compute[32008]: ERROR oslo_messaging.rpc.server   File "/opt/stack/new/nova/nova/compute/manager.py", line 6651, in attach_interface
Apr 04 00:07:20.968719 ubuntu-bionic-rax-iad-0004701322 nova-compute[32008]: ERROR oslo_messaging.rpc.server     bind_host_id=bind_host_id, tag=tag)
Apr 04 00:07:20.968719 ubuntu-bionic-rax-iad-0004701322 nova-compute[32008]: ERROR oslo_messaging.rpc.server   File "/opt/stack/new/nova/nova/network/neutronv2/api.py", line 1697, in allocate_port_for_instance
Apr 04 00:07:20.968719 ubuntu-bionic-rax-iad-0004701322 nova-compute[32008]: ERROR oslo_messaging.rpc.server     bind_host_id=bind_host_id, attach=True)
Apr 04 00:07:20.968719 ubuntu-bionic-rax-iad-0004701322 nova-compute[32008]: ERROR oslo_messaging.rpc.server   File "/opt/stack/new/nova/nova/network/neutronv2/api.py", line 1067, in allocate_for_instance
Apr 04 00:07:20.968719 ubuntu-bionic-rax-iad-0004701322 nova-compute[32008]: ERROR oslo_messaging.rpc.server     context, instance, neutron, requested_networks, ordered_networks)
Apr 04 00:07:20.968719 ubuntu-bionic-rax-iad-0004701322 nova-compute[32008]: ERROR oslo_messaging.rpc.server   File "/opt/stack/new/nova/nova/network/neutronv2/api.py", line 940, in _validate_requested_network_ids
Apr 04 00:07:20.968719 ubuntu-bionic-rax-iad-0004701322 nova-compute[32008]: ERROR oslo_messaging.rpc.server     raise exception.NetworkAmbiguous(msg)
Apr 04 00:07:20.968719 ubuntu-bionic-rax-iad-0004701322 nova-compute[32008]: ERROR oslo_messaging.rpc.server nova.exception.NetworkAmbiguous: Multiple possible networks found, use a Network ID to be more specific.
Apr 04 00:07:20.968719 ubuntu-bionic-rax-iad-0004701322 nova-compute[32008]: ERROR oslo_messaging.rpc.server 

We shouldn't traceback on this in the nova-compute logs because it's a
user-error, but we also probably shouldn't even be getting this far if
the API were validating the request body properly.

According to the API reference:

https://developer.openstack.org/api-ref/compute/?expanded=create-
interface-detail#create-interface

port_id and net_id are both optional but mutually exclusive.

The problem is both are optional because if you don't request anything,
nova-compute looks up the available network for the requesting tenant
and picks one, but if there is more than one it's an error since the
user needs to specify a port or network to use since nova can't decide
(and there is no default network - see
https://blueprints.launchpad.net/nova/+spec/deal-with-networkambiguous-
error).

So at the very least we should probably change the NetworkAmbiguous
error to a warning and not traceback.

This is an extremely latent bug so it's just marked low severity.

** Affects: nova
     Importance: Low
         Status: Triaged


** Tags: api network neutron

-- 
You received this bug notification because you are a member of Yahoo!
Engineering Team, which is subscribed to OpenStack Compute (nova).
https://bugs.launchpad.net/bugs/1823198

Title:
  NetworkAmbiguous traceback in nova-compute logs even though it's a
  user error

Status in OpenStack Compute (nova):
  Triaged

Bug description:
  There is a tempest negative test which is trying to attach a network
  interface to a server but it is not requesting a specific network or
  port:

  http://logs.openstack.org/58/637058/15/check/nova-
  next/f4e8140/logs/tempest.txt.gz#_2019-04-04_00_07_20_973

  2019-04-04 00:07:20.973 7584 INFO tempest.lib.common.rest_client [req-47bc59bc-01de-450c-9185-3c0b9dc4bf51 ] Request (AttachInterfacesTestJSON:test_create_list_show_delete_interfaces_by_network_port): 400 POST https://104.130.239.125/compute/v2.1/servers/7f24a95b-b5be-4269-980b-a92f3c07c7ca/os-interface 0.678s
  2019-04-04 00:07:20.974 7584 DEBUG tempest.lib.common.rest_client [req-47bc59bc-01de-450c-9185-3c0b9dc4bf51 ] Request - Headers: {'Content-Type': 'application/json', 'Accept': 'application/json', 'X-Auth-Token': '<omitted>'}
          Body: {"interfaceAttachment": {}}
      Response - Headers: {'date': 'Thu, 04 Apr 2019 00:07:20 GMT', 'server': 'Apache/2.4.29 (Ubuntu)', 'openstack-api-version': 'compute 2.1', 'x-openstack-nova-api-version': '2.1', 'vary': 'OpenStack-API-Version,X-OpenStack-Nova-API-Version', 'content-type': 'application/json; charset=UTF-8', 'content-length': '115', 'x-openstack-request-id': 'req-47bc59bc-01de-450c-9185-3c0b9dc4bf51', 'x-compute-request-id': 'req-47bc59bc-01de-450c-9185-3c0b9dc4bf51', 'connection': 'close', 'status': '400', 'content-location': 'https://104.130.239.125/compute/v2.1/servers/7f24a95b-b5be-4269-980b-a92f3c07c7ca/os-interface'}
          Body: b'{"badRequest": {"code": 400, "message": "Multiple possible networks found, use a Network ID to be more specific."}}' _log_request_full /opt/stack/new/tempest/tempest/lib/common/rest_client.py:440

  Which results in a NetworkAmbiguous error response from the compute
  API as seen above.

  The problem is this is a synchronous call from nova-api to nova-
  compute and results in an exception traceback in the nova-compute
  logs:

  logs.openstack.org/58/637058/15/check/nova-
  next/f4e8140/logs/screen-n-cpu.txt.gz?level=TRACE#_Apr_04_00_07_20_968719

  Apr 04 00:07:20.968719 ubuntu-bionic-rax-iad-0004701322 nova-compute[32008]: ERROR oslo_messaging.rpc.server [None req-47bc59bc-01de-450c-9185-3c0b9dc4bf51 tempest-AttachInterfacesTestJSON-791222649 tempest-AttachInterfacesTestJSON-791222649] Exception during message handling: nova.exception.NetworkAmbiguous: Multiple possible networks found, use a Network ID to be more specific.
  Apr 04 00:07:20.968719 ubuntu-bionic-rax-iad-0004701322 nova-compute[32008]: ERROR oslo_messaging.rpc.server Traceback (most recent call last):
  Apr 04 00:07:20.968719 ubuntu-bionic-rax-iad-0004701322 nova-compute[32008]: ERROR oslo_messaging.rpc.server   File "/usr/local/lib/python3.6/dist-packages/oslo_messaging/rpc/server.py", line 166, in _process_incoming
  Apr 04 00:07:20.968719 ubuntu-bionic-rax-iad-0004701322 nova-compute[32008]: ERROR oslo_messaging.rpc.server     res = self.dispatcher.dispatch(message)
  Apr 04 00:07:20.968719 ubuntu-bionic-rax-iad-0004701322 nova-compute[32008]: ERROR oslo_messaging.rpc.server   File "/usr/local/lib/python3.6/dist-packages/oslo_messaging/rpc/dispatcher.py", line 265, in dispatch
  Apr 04 00:07:20.968719 ubuntu-bionic-rax-iad-0004701322 nova-compute[32008]: ERROR oslo_messaging.rpc.server     return self._do_dispatch(endpoint, method, ctxt, args)
  Apr 04 00:07:20.968719 ubuntu-bionic-rax-iad-0004701322 nova-compute[32008]: ERROR oslo_messaging.rpc.server   File "/usr/local/lib/python3.6/dist-packages/oslo_messaging/rpc/dispatcher.py", line 194, in _do_dispatch
  Apr 04 00:07:20.968719 ubuntu-bionic-rax-iad-0004701322 nova-compute[32008]: ERROR oslo_messaging.rpc.server     result = func(ctxt, **new_args)
  Apr 04 00:07:20.968719 ubuntu-bionic-rax-iad-0004701322 nova-compute[32008]: ERROR oslo_messaging.rpc.server   File "/opt/stack/new/nova/nova/exception_wrapper.py", line 79, in wrapped
  Apr 04 00:07:20.968719 ubuntu-bionic-rax-iad-0004701322 nova-compute[32008]: ERROR oslo_messaging.rpc.server     function_name, call_dict, binary, tb)
  Apr 04 00:07:20.968719 ubuntu-bionic-rax-iad-0004701322 nova-compute[32008]: ERROR oslo_messaging.rpc.server   File "/usr/local/lib/python3.6/dist-packages/oslo_utils/excutils.py", line 220, in __exit__
  Apr 04 00:07:20.968719 ubuntu-bionic-rax-iad-0004701322 nova-compute[32008]: ERROR oslo_messaging.rpc.server     self.force_reraise()
  Apr 04 00:07:20.968719 ubuntu-bionic-rax-iad-0004701322 nova-compute[32008]: ERROR oslo_messaging.rpc.server   File "/usr/local/lib/python3.6/dist-packages/oslo_utils/excutils.py", line 196, in force_reraise
  Apr 04 00:07:20.968719 ubuntu-bionic-rax-iad-0004701322 nova-compute[32008]: ERROR oslo_messaging.rpc.server     six.reraise(self.type_, self.value, self.tb)
  Apr 04 00:07:20.968719 ubuntu-bionic-rax-iad-0004701322 nova-compute[32008]: ERROR oslo_messaging.rpc.server   File "/usr/local/lib/python3.6/dist-packages/six.py", line 693, in reraise
  Apr 04 00:07:20.968719 ubuntu-bionic-rax-iad-0004701322 nova-compute[32008]: ERROR oslo_messaging.rpc.server     raise value
  Apr 04 00:07:20.968719 ubuntu-bionic-rax-iad-0004701322 nova-compute[32008]: ERROR oslo_messaging.rpc.server   File "/opt/stack/new/nova/nova/exception_wrapper.py", line 69, in wrapped
  Apr 04 00:07:20.968719 ubuntu-bionic-rax-iad-0004701322 nova-compute[32008]: ERROR oslo_messaging.rpc.server     return f(self, context, *args, **kw)
  Apr 04 00:07:20.968719 ubuntu-bionic-rax-iad-0004701322 nova-compute[32008]: ERROR oslo_messaging.rpc.server   File "/opt/stack/new/nova/nova/compute/utils.py", line 1349, in decorated_function
  Apr 04 00:07:20.968719 ubuntu-bionic-rax-iad-0004701322 nova-compute[32008]: ERROR oslo_messaging.rpc.server     return function(self, context, *args, **kwargs)
  Apr 04 00:07:20.968719 ubuntu-bionic-rax-iad-0004701322 nova-compute[32008]: ERROR oslo_messaging.rpc.server   File "/opt/stack/new/nova/nova/compute/manager.py", line 213, in decorated_function
  Apr 04 00:07:20.968719 ubuntu-bionic-rax-iad-0004701322 nova-compute[32008]: ERROR oslo_messaging.rpc.server     kwargs['instance'], e, sys.exc_info())
  Apr 04 00:07:20.968719 ubuntu-bionic-rax-iad-0004701322 nova-compute[32008]: ERROR oslo_messaging.rpc.server   File "/usr/local/lib/python3.6/dist-packages/oslo_utils/excutils.py", line 220, in __exit__
  Apr 04 00:07:20.968719 ubuntu-bionic-rax-iad-0004701322 nova-compute[32008]: ERROR oslo_messaging.rpc.server     self.force_reraise()
  Apr 04 00:07:20.968719 ubuntu-bionic-rax-iad-0004701322 nova-compute[32008]: ERROR oslo_messaging.rpc.server   File "/usr/local/lib/python3.6/dist-packages/oslo_utils/excutils.py", line 196, in force_reraise
  Apr 04 00:07:20.968719 ubuntu-bionic-rax-iad-0004701322 nova-compute[32008]: ERROR oslo_messaging.rpc.server     six.reraise(self.type_, self.value, self.tb)
  Apr 04 00:07:20.968719 ubuntu-bionic-rax-iad-0004701322 nova-compute[32008]: ERROR oslo_messaging.rpc.server   File "/usr/local/lib/python3.6/dist-packages/six.py", line 693, in reraise
  Apr 04 00:07:20.968719 ubuntu-bionic-rax-iad-0004701322 nova-compute[32008]: ERROR oslo_messaging.rpc.server     raise value
  Apr 04 00:07:20.968719 ubuntu-bionic-rax-iad-0004701322 nova-compute[32008]: ERROR oslo_messaging.rpc.server   File "/opt/stack/new/nova/nova/compute/manager.py", line 201, in decorated_function
  Apr 04 00:07:20.968719 ubuntu-bionic-rax-iad-0004701322 nova-compute[32008]: ERROR oslo_messaging.rpc.server     return function(self, context, *args, **kwargs)
  Apr 04 00:07:20.968719 ubuntu-bionic-rax-iad-0004701322 nova-compute[32008]: ERROR oslo_messaging.rpc.server   File "/opt/stack/new/nova/nova/compute/manager.py", line 6651, in attach_interface
  Apr 04 00:07:20.968719 ubuntu-bionic-rax-iad-0004701322 nova-compute[32008]: ERROR oslo_messaging.rpc.server     bind_host_id=bind_host_id, tag=tag)
  Apr 04 00:07:20.968719 ubuntu-bionic-rax-iad-0004701322 nova-compute[32008]: ERROR oslo_messaging.rpc.server   File "/opt/stack/new/nova/nova/network/neutronv2/api.py", line 1697, in allocate_port_for_instance
  Apr 04 00:07:20.968719 ubuntu-bionic-rax-iad-0004701322 nova-compute[32008]: ERROR oslo_messaging.rpc.server     bind_host_id=bind_host_id, attach=True)
  Apr 04 00:07:20.968719 ubuntu-bionic-rax-iad-0004701322 nova-compute[32008]: ERROR oslo_messaging.rpc.server   File "/opt/stack/new/nova/nova/network/neutronv2/api.py", line 1067, in allocate_for_instance
  Apr 04 00:07:20.968719 ubuntu-bionic-rax-iad-0004701322 nova-compute[32008]: ERROR oslo_messaging.rpc.server     context, instance, neutron, requested_networks, ordered_networks)
  Apr 04 00:07:20.968719 ubuntu-bionic-rax-iad-0004701322 nova-compute[32008]: ERROR oslo_messaging.rpc.server   File "/opt/stack/new/nova/nova/network/neutronv2/api.py", line 940, in _validate_requested_network_ids
  Apr 04 00:07:20.968719 ubuntu-bionic-rax-iad-0004701322 nova-compute[32008]: ERROR oslo_messaging.rpc.server     raise exception.NetworkAmbiguous(msg)
  Apr 04 00:07:20.968719 ubuntu-bionic-rax-iad-0004701322 nova-compute[32008]: ERROR oslo_messaging.rpc.server nova.exception.NetworkAmbiguous: Multiple possible networks found, use a Network ID to be more specific.
  Apr 04 00:07:20.968719 ubuntu-bionic-rax-iad-0004701322 nova-compute[32008]: ERROR oslo_messaging.rpc.server 

  We shouldn't traceback on this in the nova-compute logs because it's a
  user-error, but we also probably shouldn't even be getting this far if
  the API were validating the request body properly.

  According to the API reference:

  https://developer.openstack.org/api-ref/compute/?expanded=create-
  interface-detail#create-interface

  port_id and net_id are both optional but mutually exclusive.

  The problem is both are optional because if you don't request
  anything, nova-compute looks up the available network for the
  requesting tenant and picks one, but if there is more than one it's an
  error since the user needs to specify a port or network to use since
  nova can't decide (and there is no default network - see
  https://blueprints.launchpad.net/nova/+spec/deal-with-
  networkambiguous-error).

  So at the very least we should probably change the NetworkAmbiguous
  error to a warning and not traceback.

  This is an extremely latent bug so it's just marked low severity.

To manage notifications about this bug go to:
https://bugs.launchpad.net/nova/+bug/1823198/+subscriptions
Follow ups

[Bug 1823198] Re: NetworkAmbiguous traceback in nova-compute logs even though it's a user error
From: OpenStack Infra, 2019-07-23
[Bug 1823198] Re: NetworkAmbiguous traceback in nova-compute logs even though it's a user error
From: Matt Riedemann, 2019-04-04