We have a use case that has to change endpoint url for a specific interface and do not want to restart service. but we fount that service seemly continued using stale endpoint info although it had been updated.
error logs are appended
```log
ConnectFailure: Unable to establish connection to http://neutron-server.openstack.svc.cn-south-1.myinspurcloud.com:9696/v2.0/ports?tenant_id=6fdf046e23d14d0a9ce52bd5b71f0afa&device_id=281925a1-ff2b-43ea-aee4-9930c3fa9df7: HTTPConnectionPool(host='neutron-server.openstack.svc.cn-south-1.myinspurcloud.com', port=9696): Max retries exceeded with url: /v2.0/ports?tenant_id=6fdf046e23d14d0a9ce52bd5b71f0afa&device_id=281925a1-ff2b-43ea-aee4-9930c3fa9df7 (Caused by NewConnectionError('<urllib3.connection.HTTPConnection object at 0x7f3f345214d0>: Failed to establish a new connection: [Errno -2] No address found',))
2021-04-01 06:28:10,344.344 47430 ERROR nova.compute.manager [instance: 281925a1-ff2b-43ea-aee4-9930c3fa9df7] Traceback (most recent call last):
2021-04-01 06:28:10,344.344 47430 ERROR nova.compute.manager [instance: 281925a1-ff2b-43ea-aee4-9930c3fa9df7] File "/usr/lib/python2.7/dist-packages/nova/compute/manager.py", line 6843, in _heal_instance_info_cache
2021-04-01 06:28:10,344.344 47430 ERROR nova.compute.manager [instance: 281925a1-ff2b-43ea-aee4-9930c3fa9df7] self.network_api.get_instance_nw_info(context, instance)
2021-04-01 06:28:10,344.344 47430 ERROR nova.compute.manager [instance: 281925a1-ff2b-43ea-aee4-9930c3fa9df7] File "/usr/lib/python2.7/dist-packages/nova/network/base_api.py", line 249, in get_instance_nw_info
2021-04-01 06:28:10,344.344 47430 ERROR nova.compute.manager [instance: 281925a1-ff2b-43ea-aee4-9930c3fa9df7] result = self._get_instance_nw_info(context, instance, **kwargs)
2021-04-01 06:28:10,344.344 47430 ERROR nova.compute.manager [instance: 281925a1-ff2b-43ea-aee4-9930c3fa9df7] File "/usr/lib/python2.7/dist-packages/nova/network/neutronv2/api.py", line 1481, in _get_instance_nw_info
2021-04-01 06:28:10,344.344 47430 ERROR nova.compute.manager [instance: 281925a1-ff2b-43ea-aee4-9930c3fa9df7] refresh_vif_id)
2021-04-01 06:28:10,344.344 47430 ERROR nova.compute.manager [instance: 281925a1-ff2b-43ea-aee4-9930c3fa9df7] File "/usr/lib/python2.7/dist-packages/nova/network/neutronv2/api.py", line 2481, in _build_network_info_model
2021-04-01 06:28:10,344.344 47430 ERROR nova.compute.manager [instance: 281925a1-ff2b-43ea-aee4-9930c3fa9df7] data = client.list_ports(**search_opts)
2021-04-01 06:28:10,344.344 47430 ERROR nova.compute.manager [instance: 281925a1-ff2b-43ea-aee4-9930c3fa9df7] File "/usr/lib/python2.7/dist-packages/nova/network/neutronv2/api.py", line 122, in wrapper
2021-04-01 06:28:10,344.344 47430 ERROR nova.compute.manager [instance: 281925a1-ff2b-43ea-aee4-9930c3fa9df7] ret = obj(*args, **kwargs)
2021-04-01 06:28:10,344.344 47430 ERROR nova.compute.manager [instance: 281925a1-ff2b-43ea-aee4-9930c3fa9df7] File "/usr/lib/python2.7/dist-packages/neutronclient/v2_0/client.py", line 794, in list_ports
2021-04-01 06:28:10,344.344 47430 ERROR nova.compute.manager [instance: 281925a1-ff2b-43ea-aee4-9930c3fa9df7] **_params)
2021-04-01 06:28:10,344.344 47430 ERROR nova.compute.manager [instance: 281925a1-ff2b-43ea-aee4-9930c3fa9df7] File "/usr/lib/python2.7/dist-packages/nova/network/neutronv2/api.py", line 122, in wrapper
2021-04-01 06:28:10,344.344 47430 ERROR nova.compute.manager [instance: 281925a1-ff2b-43ea-aee4-9930c3fa9df7] ret = obj(*args, **kwargs)
2021-04-01 06:28:10,344.344 47430 ERROR nova.compute.manager [instance: 281925a1-ff2b-43ea-aee4-9930c3fa9df7] File "/usr/lib/python2.7/dist-packages/neutronclient/v2_0/client.py", line 369, in list
2021-04-01 06:28:10,344.344 47430 ERROR nova.compute.manager [instance: 281925a1-ff2b-43ea-aee4-9930c3fa9df7] for r in self._pagination(collection, path, **params):
2021-04-01 06:28:10,344.344 47430 ERROR nova.compute.manager [instance: 281925a1-ff2b-43ea-aee4-9930c3fa9df7] File "/usr/lib/python2.7/dist-packages/neutronclient/v2_0/client.py", line 384, in _pagination
2021-04-01 06:28:10,344.344 47430 ERROR nova.compute.manager [instance: 281925a1-ff2b-43ea-aee4-9930c3fa9df7] res = self.get(path, params=params)
2021-04-01 06:28:10,344.344 47430 ERROR nova.compute.manager [instance: 281925a1-ff2b-43ea-aee4-9930c3fa9df7] File "/usr/lib/python2.7/dist-packages/nova/network/neutronv2/api.py", line 122, in wrapper
2021-04-01 06:28:10,344.344 47430 ERROR nova.compute.manager [instance: 281925a1-ff2b-43ea-aee4-9930c3fa9df7] ret = obj(*args, **kwargs)
2021-04-01 06:28:10,344.344 47430 ERROR nova.compute.manager [instance: 281925a1-ff2b-43ea-aee4-9930c3fa9df7] File "/usr/lib/python2.7/dist-packages/neutronclient/v2_0/client.py", line 354, in get
2021-04-01 06:28:10,344.344 47430 ERROR nova.compute.manager [instance: 281925a1-ff2b-43ea-aee4-9930c3fa9df7] headers=headers, params=params)
2021-04-01 06:28:10,344.344 47430 ERROR nova.compute.manager [instance: 281925a1-ff2b-43ea-aee4-9930c3fa9df7] File "/usr/lib/python2.7/dist-packages/nova/network/neutronv2/api.py", line 122, in wrapper
2021-04-01 06:28:10,344.344 47430 ERROR nova.compute.manager [instance: 281925a1-ff2b-43ea-aee4-9930c3fa9df7] ret = obj(*args, **kwargs)
2021-04-01 06:28:10,344.344 47430 ERROR nova.compute.manager [instance: 281925a1-ff2b-43ea-aee4-9930c3fa9df7] File "/usr/lib/python2.7/dist-packages/neutronclient/v2_0/client.py", line 331, in retry_request
2021-04-01 06:28:10,344.344 47430 ERROR nova.compute.manager [instance: 281925a1-ff2b-43ea-aee4-9930c3fa9df7] headers=headers, params=params)
2021-04-01 06:28:10,344.344 47430 ERROR nova.compute.manager [instance: 281925a1-ff2b-43ea-aee4-9930c3fa9df7] File "/usr/lib/python2.7/dist-packages/nova/network/neutronv2/api.py", line 122, in wrapper
2021-04-01 06:28:10,344.344 47430 ERROR nova.compute.manager [instance: 281925a1-ff2b-43ea-aee4-9930c3fa9df7] ret = obj(*args, **kwargs)
2021-04-01 06:28:10,344.344 47430 ERROR nova.compute.manager [instance: 281925a1-ff2b-43ea-aee4-9930c3fa9df7] File "/usr/lib/python2.7/dist-packages/neutronclient/v2_0/client.py", line 282, in do_request
2021-04-01 06:28:10,344.344 47430 ERROR nova.compute.manager [instance: 281925a1-ff2b-43ea-aee4-9930c3fa9df7] headers=headers)
2021-04-01 06:28:10,344.344 47430 ERROR nova.compute.manager [instance: 281925a1-ff2b-43ea-aee4-9930c3fa9df7] File "/usr/lib/python2.7/dist-packages/neutronclient/client.py", line 343, in do_request
2021-04-01 06:28:10,344.344 47430 ERROR nova.compute.manager [instance: 281925a1-ff2b-43ea-aee4-9930c3fa9df7] return self.request(url, method, **kwargs)
2021-04-01 06:28:10,344.344 47430 ERROR nova.compute.manager [instance: 281925a1-ff2b-43ea-aee4-9930c3fa9df7] File "/usr/lib/python2.7/dist-packages/neutronclient/client.py", line 331, in request
2021-04-01 06:28:10,344.344 47430 ERROR nova.compute.manager [instance: 281925a1-ff2b-43ea-aee4-9930c3fa9df7] resp = super(SessionClient, self).request(*args, **kwargs)
2021-04-01 06:28:10,344.344 47430 ERROR nova.compute.manager [instance: 281925a1-ff2b-43ea-aee4-9930c3fa9df7] File "/usr/lib/python2.7/dist-packages/keystoneauth1/adapter.py", line 189, in request
2021-04-01 06:28:10,344.344 47430 ERROR nova.compute.manager [instance: 281925a1-ff2b-43ea-aee4-9930c3fa9df7] return self.session.request(url, method, **kwargs)
2021-04-01 06:28:10,344.344 47430 ERROR nova.compute.manager [instance: 281925a1-ff2b-43ea-aee4-9930c3fa9df7] File "/usr/lib/python2.7/dist-packages/keystoneauth1/session.py", line 698, in request
2021-04-01 06:28:10,344.344 47430 ERROR nova.compute.manager [instance: 281925a1-ff2b-43ea-aee4-9930c3fa9df7] resp = send(**kwargs)
2021-04-01 06:28:10,344.344 47430 ERROR nova.compute.manager [instance: 281925a1-ff2b-43ea-aee4-9930c3fa9df7] File "/usr/lib/python2.7/dist-packages/keystoneauth1/session.py", line 772, in _send_request
2021-04-01 06:28:10,344.344 47430 ERROR nova.compute.manager [instance: 281925a1-ff2b-43ea-aee4-9930c3fa9df7] raise exceptions.ConnectFailure(msg)
2021-04-01 06:28:10,344.344 47430 ERROR nova.compute.manager [instance: 281925a1-ff2b-43ea-aee4-9930c3fa9df7] ConnectFailure: Unable to establish connection to http://neutron-server.openstack.svc.cn-south-1.myinspurcloud.com:9696/v2.0/ports?tenant_id=6fdf046e23d14d0a9ce52bd5b71f0afa&device_id=281925a1-ff2b-43ea-aee4-9930c3fa9df7: HTTPConnectionPool(host='neutron-server.openstack.svc.cn-south-1.myinspurcloud.com', port=9696): Max retries exceeded with url: /v2.0/ports?tenant_id=6fdf046e23d14d0a9ce52bd5b71f0afa&device_id=281925a1-ff2b-43ea-aee4-9930c3fa9df7 (Caused by NewConnectionError('<urllib3.connection.HTTPConnection object at 0x7f3f345214d0>: Failed to establish a new connection: [Errno -2] No address found',))
```