[OVN] Inconsistent "flooding to unregistered" IGMP configuration

[Lucas Alvares Gomes]

ML2/OVN reuses the same "[ovs]/igmp_snooping_enable" configuration option from ML2/OVS, which says [0]:

"Setting this option to True will also enable Open vSwitch mcast-snooping-disable-flood-unregistered flag. This option will disable flooding of unregistered multicast packets to all ports."

But, that's not true for ML2/OVN, in fact, this is the opposite because ML2/OVN does have the option to flood to unregistered VMs enabled by default.

In order to keep the consistent between both drivers and this configuration option, ML2/OVN needs to disable the "mcast_flood_unregistered" configuration in the other_config column from the Logical Switch table when igmp_snooping_enable is True.

[0] https://opendev.org/openstack/neutron/src/branch/master/neutron/conf/agent/ovs_conf.py#L36-L47

[Impact]

See above.

[Test Case]

Run the following and expect success:
root@f1:~# sudo apt install python3-neutron
root@f1:/usr/lib/python3/dist-packages# python3 -m unittest neutron.tests.unit.plugins.ml2.drivers.ovn.mech_driver.ovsdb.test_maintenance.TestDBInconsistenciesPeriodics.test_check_for_igmp_snoop_support

I would also like to get test feedback from Canonical bootstack as they are hitting this issue.

[Regression Potential]
This is a very minimal and targeted change that always hard codes MCAST_FLOOD_UNREGISTERED to 'false'.

In assessing regression potential for changes like this, one that comes to mind is potential of a type error when setting MCAST_FLOOD_UNREGISTERED. Upon visual inspection of this code fix, a type error would be impossible, as what was once set to a 'true' or 'false' value is now set to 'false'.

Another thought is whether MCAST_FLOOD_UNREGISTERED has any use if MCAST_SNOOP is set to false, but that is not the case according to upstream OVN documentation which states: mcast_flood_unregistered: optional string, either true or false Determines whether unregistered multicast traffic should be flooded or not. Only applicable if other_config:mcast_snoop is enabled.

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.opendev.org/762818

[OpenStack Infra (hudson-openstack)]

This issue was fixed in the openstack/neutron 16.3.0 release.

[OpenStack Infra (hudson-openstack)]

This issue was fixed in the openstack/neutron 17.1.0 release.

[Corey Bryant (corey.bryant)]

New versions of neutron containing this fix have been uploaded to the groovy and focal unapproved queue where they are awaiting SRU team review.

[Brian Murray (brian-murray)]

Hello Lucas, or anyone else affected,

Accepted neutron into groovy-proposed. The package will build now and be available at https://launchpad.net/ubuntu/+source/neutron/2:17.0.0-0ubuntu3 in a few hours, and then in the -proposed repository.

Please help us by testing this new package. See https://wiki.ubuntu.com/Testing/EnableProposed for documentation on how to enable and use -proposed. Your feedback will aid us getting this update out to other Ubuntu users.

If this package fixes the bug for you, please add a comment to this bug, mentioning the version of the package you tested, what testing has been performed on the package and change the tag from verification-needed-groovy to verification-done-groovy. If it does not fix the bug for you, please add a comment stating that, and change the tag to verification-failed-groovy. In either case, without details of your testing we will not be able to proceed.

Further information regarding the verification process can be found at https://wiki.ubuntu.com/QATeam/PerformingSRUVerification . Thank you in advance for helping!

N.B. The updated package will be released to -updates after the bug(s) fixed by this package have been verified and the package has been in -proposed for a minimum of 7 days.

[Brian Murray (brian-murray)]

Hello Lucas, or anyone else affected,

Accepted neutron into focal-proposed. The package will build now and be available at https://launchpad.net/ubuntu/+source/neutron/2:16.2.0-0ubuntu3 in a few hours, and then in the -proposed repository.

Please help us by testing this new package. See https://wiki.ubuntu.com/Testing/EnableProposed for documentation on how to enable and use -proposed. Your feedback will aid us getting this update out to other Ubuntu users.

If this package fixes the bug for you, please add a comment to this bug, mentioning the version of the package you tested, what testing has been performed on the package and change the tag from verification-needed-focal to verification-done-focal. If it does not fix the bug for you, please add a comment stating that, and change the tag to verification-failed-focal. In either case, without details of your testing we will not be able to proceed.

Further information regarding the verification process can be found at https://wiki.ubuntu.com/QATeam/PerformingSRUVerification . Thank you in advance for helping!

N.B. The updated package will be released to -updates after the bug(s) fixed by this package have been verified and the package has been in -proposed for a minimum of 7 days.

[Corey Bryant (corey.bryant)]

Hello Lucas, or anyone else affected,

Accepted neutron into victoria-proposed. The package will build now and be available in the Ubuntu Cloud Archive in a few hours, and then in the -proposed repository.

Please help us by testing this new package. To enable the -proposed repository:

  sudo add-apt-repository cloud-archive:victoria-proposed
  sudo apt-get update

Your feedback will aid us getting this update out to other Ubuntu users.

If this package fixes the bug for you, please add a comment to this bug, mentioning the version of the package you tested, and change the tag from verification-victoria-needed to verification-victoria-done. If it does not fix the bug for you, please add a comment stating that, and change the tag to verification-victoria-failed. In either case, details of your testing will help us make a better decision.

Further information regarding the verification process can be found at https://wiki.ubuntu.com/QATeam/PerformingSRUVerification . Thank you in advance!

[Corey Bryant (corey.bryant)]

Hello Lucas, or anyone else affected,

Accepted neutron into ussuri-proposed. The package will build now and be available in the Ubuntu Cloud Archive in a few hours, and then in the -proposed repository.

Please help us by testing this new package. To enable the -proposed repository:

  sudo add-apt-repository cloud-archive:ussuri-proposed
  sudo apt-get update

Your feedback will aid us getting this update out to other Ubuntu users.

If this package fixes the bug for you, please add a comment to this bug, mentioning the version of the package you tested, and change the tag from verification-ussuri-needed to verification-ussuri-done. If it does not fix the bug for you, please add a comment stating that, and change the tag to verification-ussuri-failed. In either case, details of your testing will help us make a better decision.

Further information regarding the verification process can be found at https://wiki.ubuntu.com/QATeam/PerformingSRUVerification . Thank you in advance!

[Corey Bryant (corey.bryant)]

Testcases successful (see below). I would also like to get bootstack feedback before tagging this as verified.

== groovy-proposed ==
root@g1:/usr/lib/python3/dist-packages# python3 -m unittest neutron.tests.unit.plugins.ml2.drivers.ovn.mech_driver.ovsdb.test_maintenance.TestDBInconsistenciesPeriodics.test_check_for_igmp_snoop_support
Could not load 'oslo_cache.etcd3gw': No module named 'etcd3gw'
/usr/lib/python3/dist-packages/sqlalchemy/orm/relationships.py:1993: SAWarning: Setting backref / back_populates on relationship QosNetworkPolicyBinding.port to refer to viewonly relationship Port.qos_network_policy_binding should include sync_backref=False set on the QosNetworkPolicyBinding.port relationship. (this warning may be suppressed after 10 occurrences)
  util.warn_limited(
/usr/lib/python3/dist-packages/sqlalchemy/orm/relationships.py:1993: SAWarning: Setting backref / back_populates on relationship Tag.standard_attr to refer to viewonly relationship StandardAttribute.tags should include sync_backref=False set on the Tag.standard_attr relationship. (this warning may be suppressed after 10 occurrences)
  util.warn_limited(
/usr/lib/python3/dist-packages/neutron_lib/context.py:151: DeprecationWarning: context.session is used with and without new enginefacade. Please update the code to use new enginefacede consistently.
  warnings.warn('context.session is used with and without '
.
----------------------------------------------------------------------
Ran 1 test in 1.716s

OK
root@g1:/usr/lib/python3/dist-packages# apt policy python3-neutron
python3-neutron:
  Installed: 2:17.0.0-0ubuntu3
  Candidate: 2:17.0.0-0ubuntu3
  Version table:
 *** 2:17.0.0-0ubuntu3 500
        500 http://archive.ubuntu.com/ubuntu groovy-proposed/main amd64 Packages

== focal-proposed ==
root@f1:/usr/lib/python3/dist-packages# python3 -m unittest neutron.tests.unit.plugins.ml2.drivers.ovn.mech_driver.ovsdb.test_maintenance.TestDBInconsistenciesPeriodics.test_check_for_igmp_snoop_support
/usr/lib/python3/dist-packages/neutron_lib/context.py:151: DeprecationWarning: context.session is used with and without new enginefacade. Please update the code to use new enginefacede consistently.
  warnings.warn('context.session is used with and without '
.
----------------------------------------------------------------------
Ran 1 test in 2.692s

OK
root@f1:/usr/lib/python3/dist-packages# python3 -m unittest neutron.tests.unit.plugins.ml2.drivers.ovn.mech_driver.ovsdb.test_maintenance.TestDBInconsistenciesPeriodics.test_check_for_igmp_snoop_support^C
root@f1:/usr/lib/python3/dist-packages# apt policy python3-neutron
python3-neutron:
  Installed: 2:16.2.0-0ubuntu3
  Candidate: 2:16.2.0-0ubuntu3
  Version table:
 *** 2:16.2.0-0ubuntu3 500
        500 http://archive.ubuntu.com/ubuntu focal-proposed/main amd64 Packages

== victoria-proposed ==
root@fv:/usr/lib/python3/dist-packages# python3 -m unittest neutron.tests.unit.plugins.ml2.drivers.ovn.mech_driver.ovsdb.test_maintenance.TestDBInconsistenciesPeriodics.test_check_for_igmp_snoop_support
Could not load 'oslo_cache.etcd3gw': No module named 'etcd3gw'
/usr/lib/python3/dist-packages/sqlalchemy/orm/relationships.py:1993: SAWarning...

[Chris Halse Rogers (raof)]

This is now blocking the acceptance of the 17.1.0 SRU from unapproved for both focal and groovy. Could someone please do the SRU testing for this package?

[Łukasz Zemczak (sil2100)]

The verification of the Stable Release Update for neutron has completed successfully and the package is now being released to -updates. Subsequently, the Ubuntu Stable Release Updates Team is being unsubscribed and will not receive messages about this bug report. In the event that you encounter a regression using the package from -updates please report a new bug using ubuntu-bug and tag the bug report regression-update so we can easily find any regressions.

[Launchpad Janitor (janitor)]

This bug was fixed in the package neutron - 2:17.0.0-0ubuntu3

---------------
neutron (2:17.0.0-0ubuntu3) groovy; urgency=medium

  * d/p/ovn-fix-inconsistent-igmp-configuration.patch: Cherry-picked from
    upstream stable/victoria to ensure flooding of unregistered multicast
    packets to all ports is disabled (LP: #1904399).

 -- Corey Bryant <email address hidden> Mon, 08 Feb 2021 12:25:46 -0500

[Launchpad Janitor (janitor)]

This bug was fixed in the package neutron - 2:16.2.0-0ubuntu3

---------------
neutron (2:16.2.0-0ubuntu3) focal; urgency=medium

  * d/p/ovn-fix-inconsistent-igmp-configuration.patch: Cherry-picked from
    upstream stable/ussuri to ensure flooding of unregistered multicast
    packets to all ports is disabled (LP: #1904399).

 -- Corey Bryant <email address hidden> Mon, 08 Feb 2021 12:31:39 -0500

[Corey Bryant (corey.bryant)]

The verification of the Stable Release Update for neutron has completed successfully and the package has now been released to -updates. In the event that you encounter a regression using the package from -updates please report a new bug using ubuntu-bug and tag the bug report regression-update so we can easily find any regressions.

[Corey Bryant (corey.bryant)]

This bug was fixed in the package neutron - 2:17.0.0-0ubuntu3~cloud0
---------------

 neutron (2:17.0.0-0ubuntu3~cloud0) focal-victoria; urgency=medium
 .
   * New update for the Ubuntu Cloud Archive.
 .
 neutron (2:17.0.0-0ubuntu3) groovy; urgency=medium
 .
   * d/p/ovn-fix-inconsistent-igmp-configuration.patch: Cherry-picked from
     upstream stable/victoria to ensure flooding of unregistered multicast
     packets to all ports is disabled (LP: #1904399).

[Corey Bryant (corey.bryant)]

The verification of the Stable Release Update for neutron has completed successfully and the package has now been released to -updates. In the event that you encounter a regression using the package from -updates please report a new bug using ubuntu-bug and tag the bug report regression-update so we can easily find any regressions.

[Corey Bryant (corey.bryant)]

This bug was fixed in the package neutron - 2:16.2.0-0ubuntu3~cloud0
---------------

 neutron (2:16.2.0-0ubuntu3~cloud0) bionic-ussuri; urgency=medium
 .
   * New update for the Ubuntu Cloud Archive.
 .
 neutron (2:16.2.0-0ubuntu3) focal; urgency=medium
 .
   * d/p/ovn-fix-inconsistent-igmp-configuration.patch: Cherry-picked from
     upstream stable/ussuri to ensure flooding of unregistered multicast
     packets to all ports is disabled (LP: #1904399).

[OpenStack Infra (hudson-openstack)]

This issue was fixed in the openstack/networking-ovn 7.4.0 release.

[OpenStack Infra (hudson-openstack)]

This issue was fixed in the openstack/neutron 18.0.0.0rc1 release candidate.