Functional tests neutron.tests.functional.agent.linux.test_linuxbridge_arp_protect failing on Ubuntu 20.04

[Slawek Kaplonski]

We are going to switch our testing to the Ubuntu 20.04 and some functional tests from module neutron.tests.functional.agent.linux.test_linuxbridge_arp_protect are failing there.

Errors are like: http://paste.openstack.org/show/796490/

[Slawek Kaplonski (slaweq)]

According to e.g. comment in https://serverfault.com/questions/726764/migration-of-ebtables-arp-rule-to-nftables it seems that nftables have no implemented syntax for source and destination ipv4 address in arp tables right now.

So solution/workaround for this issue for us would be to switch to ebtables-legacy on Ubuntu Focal, at least for now.

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.opendev.org/744500

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.opendev.org/744500
Committed: https://git.openstack.org/cgit/openstack/neutron/commit/?id=31a95c085fc1a5ce8a57ff834386b022ae087e24
Submitter: Zuul
Branch: master

commit 31a95c085fc1a5ce8a57ff834386b022ae087e24
Author: Slawek Kaplonski <email address hidden>
Date: Mon Aug 3 16:58:05 2020 +0200

    Use ebtables-legacy on Ubuntu Focal

    On Ubuntu 20.04 there is by default ebtables-nft used. The problem with
    that is that nftables don't supports syntax for source and destination
    ipv4 address in arp tables right now.
    So to workaround/fix this problem at least in our gate jobs we have to
    switch to ebtables-legacy for now.
    And that's exactly what this patch is doing.

    Change-Id: I0aca119f1feca1d8f31a0104dde40d5d52c1b25c
    Closes-Bug: #1889779