Comment 30 for bug 1931133

Reviewed: https://review.opendev.org/c/openstack/tripleo-heat-templates/+/804515
Committed: https://opendev.org/openstack/tripleo-heat-templates/commit/3d4063fcabe442d2aae527d51b3802b01f3056ab
Submitter: "Zuul (22348)"
Branch: stable/ussuri

commit 3d4063fcabe442d2aae527d51b3802b01f3056ab
Author: Michele Baldessari <email address hidden>
Date: Wed Aug 11 15:55:22 2021 +0200

    OVN DBs clustering

    We introduce support for running both the NB and SB OVN databases in
    clustered mode. This OVN DBs clustered mode is based on OVNs own
    clustering protocol and does not rely on pacemaker.

    Clustering the two OVN databases increases reliability. The cluster
    works in active-active mode and has the potential to be more
    resilient and performant.

    See
    https://docs.openvswitch.org/en/latest/ref/ovsdb.7/#clustered-database-service-model
    for more information.

    For backport simplicity we also add I50cf3b7d79d8cd139ae514438e147df73901a366
    ("Fix typo in ovn-dbs-cluster northd kolla config file") which
    is a cherry-pick + squash of commit 1115698c14788555510edbe1760bbc9cc9110dff,
    so we avoid ovn_northd connecting only to the local db via unix socket.

    Co-Authored-By: Michele Baldessari <email address hidden>

    Related-Bug: #1931133
    Depends-On: https://review.opendev.org/c/openstack/tripleo-ansible/+/804435
    Depends-On: https://review.opendev.org/c/openstack/puppet-tripleo/+/795763

    NB: Some changes for this ussuri (just like for victoria) backport are needed:
    - Readd DefaultPasswords:
    - go back to the old way of doing TLS (i.e. no system-roles.certificate)
    - template version back to rocky
    - Set tripleo_container_manage_systemd_order: false (I believe it was a
      mistake to start with and we removed it in master as well)

    Change-Id: I59bfe69dbb5f3d525ac6f6d655577d24036328c0
    (cherry picked from commit baf4a16149d2a31ccb331cc96b89871e71c00734)
    (cherry picked from commit 15433f131ceee8e8df6e8ca60b0703467fbbf310)
    (cherry picked from commit 40da6ed23462369add64c9c2907926eb632816d0)