Comment 3 for bug 1834856

Reviewed: https://review.opendev.org/668462
Committed: https://git.openstack.org/cgit/openstack/tripleo-heat-templates/commit/?id=8775e2d5aa3e29137aadd2419ca89fbec4beb499
Submitter: Zuul
Branch: master

commit 8775e2d5aa3e29137aadd2419ca89fbec4beb499
Author: Michele Baldessari <email address hidden>
Date: Mon Jul 1 14:52:21 2019 +0200

    Fix ovn dbs control port

    When an OCF bundle is managed by pacemaker it runs pacemaker-remote
    inside the container. The communication between the pacemaker cluster
    and the remote happens through a so-called control port. In the case of
    ovn-dbs, this port is set to 3125 by default:
    https://github.com/openstack/puppet-tripleo/blob/master/manifests/profile/pacemaker/ovn_dbs_bundle.pp#L62

    We need to make sure that the cluster is always able to connect to said
    port as the connection might come from a cluster node that is not the
    same node where the ovn bundle is running.

    This has worked so far only by pure luck because pacemaker will retry
    the connection from each controller node and eventually when the
    connection comes from the same host as the one where the bundle is
    running it succeeds (INPUT rules do not apply to same-host connections).

    Tested and correctly observed port 3125/tcp being open in iptables:
    * Before
    [root@controller-0]# iptables -nvL INPUT |grep 3125
    [root@controller-0]#

    * After
    [root@controller-0]# iptables -nvL INPUT |grep 3125
        0 0 ACCEPT tcp -- * * 0.0.0.0/0 0.0.0.0/0 multiport dports 3125,6641,6642 state NEW /* 121 OVN DB server ports ipv4 */

    Closes-Bug: #1834856
    Change-Id: Ia455702d75a450f1c3ac88ed69853e9b98b98644