Comment 6 for bug 1866937

Reviewed: https://review.opendev.org/722077
Committed: https://git.openstack.org/cgit/openstack/nova/commit/?id=a96e7ab83066bee0a13a54070aab988396bae320
Submitter: Zuul
Branch: stable/stein

commit a96e7ab83066bee0a13a54070aab988396bae320
Author: melanie witt <email address hidden>
Date: Wed Mar 11 02:26:52 2020 +0000

    Add config option for neutron client retries

    Nova can occasionally fail to carry out server actions which require
    calls to neutron API if haproxy happens to close a connection after
    idle time if an incoming request attempts to re-use the connection
    while it is being torn down.

    In order to be more resilient to this scenario, we can add a config
    option for neutron client to retry requests, similar to our existing
    CONF.cinder.http_retries and CONF.glance.num_retries options.

    Because we create our neutron client [1] using a keystoneauth1 session
    [2], we can set the 'connect_retries' keyword argument to let
    keystoneauth1 handle connection retries.

    Closes-Bug: #1866937

    [1] https://github.com/openstack/nova/blob/57459c3429ce62975cebd0cd70936785bdf2f3a4/nova/network/neutron.py#L226-L237
    [2] https://docs.openstack.org/keystoneauth/latest/api/keystoneauth1.session.html#keystoneauth1.session.Session

    Change-Id: Ifb3afb13aff7e103c2e80ade817d0e63b624604a
    (cherry picked from commit 0e34ed9733e3f23d162e3e428795807386abf1cb)
    (cherry picked from commit 71971c206292232fff389dedbf412d780f0a557a)