NetlinkError 'Operation not supported'

[hongbin]

Kuryr occasionally failed with the following error:

  "NetlinkError: (95, 'Operation not supported')"

This happened only on the gate, and it is random. I couldn't reproduce it locally. Here is the full trace:

  http://paste.openstack.org/show/723038/

Here is gate log:

  http://logs.openstack.org/52/574052/1/check/zun-tempest-docker-etcd/200e9b9/logs/screen-kuryr-libnetwork.txt.gz#_Jun_09_20_43_12_194567

logstash:

  http://logstash.openstack.org/#dashboard/file/logstash.json?query=message%3A%5C%22Operation%20not%20supported%5C%22%20AND%20tags%3A%5C%22screen-kuryr-libnetwork.txt%5C%22