ovn upgrades should finish with unsetting ovn-match-northd-version

[Edward Hope-Morley]

The charms will set ovn-match-northd-version=true in ovn-chassis ovsdb to support major release upgrades but it will not be unset at any point. This will mean that minor release upgrades will result in northd version mismatch errors and an ovn-controller failing to connect to the southbound db. The next release of the charms will have https://bugs.launchpad.net/charm-ovn-chassis/+bug/2030944 i.e. a new config option to make this configurable. We should add a final action to the charm-guide(s) for ovn upgrade ops to have this flag set back to false.

[Alan Baghumian (alanbach)]

Hi Ed,

Thank you for filing this bug.

I totally agree and we have seen this happening many times over. Different units might get the minor release updates at different times and this should not break connectivity. Automatically setting ovn-match-northd-version=false post upgrades will prevent this.

Best,
Alan

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.opendev.org/c/openstack/charm-guide/+/899892

[OpenStack Infra (hudson-openstack)]

Change abandoned by "Peter Matulis <email address hidden>" on branch: master
Review: https://review.opendev.org/c/openstack/charm-guide/+/899892
Reason: superseded by 4e081814a0df2e11aeb4f61775b549828fdeaf89

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.opendev.org/c/openstack/charm-guide/+/903743
Committed: https://opendev.org/openstack/charm-guide/commit/2099dfd654ad09961744967ddef8236c9294b0fb
Submitter: "Zuul (22348)"
Branch: master

commit 2099dfd654ad09961744967ddef8236c9294b0fb
Author: Frode Nordahl <email address hidden>
Date: Fri Dec 15 10:17:37 2023 +0100

    Advise user to disable version pinning after upgrade

    Now that the ovn-chassis charm has the ``enable-version-pinning``
    configuration option, which has been backported to the 22.03 charm,
    advise user to disable version pinning after completing the 20.03
    to 22.03 upgrade.

    pmatulis:

    * Clarify wording around versions and upgrades.
    * Add a table of contents due to the length of this page.

    Related-Bug: #2030944
    Closes-Bug: #2042478
    Signed-off-by: Frode Nordahl <email address hidden>
    Change-Id: I4e081814a0df2e11aeb4f61775b549828fdeaf89