Upstream will deprecate usage of eventlet of all the WSGI-run services, including nova-api and nova-metadata-api.
See https://review.openstack.org/#/c/549510/ for more details.
OSP13 runs nova-api through HTTPd already , so we're clear for the the former, but the latter (nova-metadata-api) requires a bit of work .
To make it clear, given upstream change, our customers would see a warning in the metadata service logs if we don't fix that for OSP14, which I guess is a bad experience for them as it could confuse them.
Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.
For information on the advisory, and where to find the updated
files, follow the link below.
If the solution does not work for you, open a new bug report.