From e860b9580c708ef8fb810f95563ec1f956952bb1 Mon Sep 17 00:00:00 2001
From: Jakub Libosvar <libosvar@redhat.com>
Date: Mon, 13 Nov 2017 13:25:47 +0000
Subject: [PATCH] neutron: Call destroy-patch-ports before starting ovs-agent

The script called destroy-patch-ports will break connection between the
integration bridge and provider bridges configured in Neutron config
files. See https://bugzilla.redhat.com/show_bug.cgi?id=1490281 for more
details about the reason.

With systemd, we have control over dependencies between services,
therefore we can tell that destroy-patch-ports service must be run
before neutron-openvswitch-agent. But we do not have this ability using
docker. That's why this patch simply calls the script before each start
of the agent. To avoid unnecessary breakage of patch ports, the script
was enhanced to check a canary flow on integration bridge and in case
the flow is there, it will not delete the patch ports. Presence of
canary flow on integration bridge means that bridge has been already
configured. It also implies provider bridges are configured too and thus
they can't cause the ARP storm as described in Red Hat Bugzilla 1490281.

NOTE: This patch requires the packaging side to be merged first:
      https://review.rdoproject.org/r/#/c/10480/

Co-Authored-By: Dan Prince <dprince@redhat.com>

Closes-bug: #1731924

Change-Id: I005af23b1815c904ef63676553df9b14b7edfbfc
---
 docker/services/neutron-ovs-agent.yaml | 15 ++++++++++-----
 1 file changed, 10 insertions(+), 5 deletions(-)

diff --git a/docker/services/neutron-ovs-agent.yaml b/docker/services/neutron-ovs-agent.yaml
index 9d0b92cd42..ceff8653fb 100644
--- a/docker/services/neutron-ovs-agent.yaml
+++ b/docker/services/neutron-ovs-agent.yaml
@@ -88,11 +88,7 @@ outputs:
           - /run/openvswitch:/run/openvswitch
       kolla_config:
         /var/lib/kolla/config_files/neutron_ovs_agent.json:
-          command:
-            list_join:
-              - ' '
-              - - /usr/bin/neutron-openvswitch-agent --config-file /usr/share/neutron/neutron-dist.conf --config-file /etc/neutron/neutron.conf --config-file /etc/neutron/plugins/ml2/openvswitch_agent.ini --config-file /etc/neutron/plugins/ml2/ml2_conf.ini --config-dir /etc/neutron/conf.d/common
-                - get_attr: [NeutronLogging, cmd_extra_args]
+          command: /neutron_ovs_agent_launcher.sh
           config_files:
             - source: "/var/lib/kolla/config_files/src/*"
               dest: "/"
@@ -102,6 +98,14 @@ outputs:
             - path: /var/log/neutron
               owner: neutron:neutron
               recurse: true
+      docker_config_scripts:
+        neutron_ovs_agent_launcher.sh:
+          mode: "0755"
+          content: |
+            #!/bin/bash
+            set -xe
+            /usr/bin/python -m neutron.cmd.destroy_patch_ports --config-file /usr/share/neutron/neutron-dist.conf --config-file /etc/neutron/neutron.conf --config-file /etc/neutron/plugins/ml2/openvswitch_agent.ini --config-dir /etc/neutron/conf.d/common --config-dir /etc/neutron/conf.d/neutron-openvswitch-agent
+            /usr/bin/neutron-openvswitch-agent --config-file /usr/share/neutron/neutron-dist.conf --config-file /etc/neutron/neutron.conf --config-file /etc/neutron/plugins/ml2/openvswitch_agent.ini --config-file /etc/neutron/plugins/ml2/ml2_conf.ini --config-dir /etc/neutron/conf.d/common --log-file=/var/log/neutron/openvswitch-agent.log
       docker_config:
         step_3:
           neutron_ovs_bridge:
@@ -151,6 +155,7 @@ outputs:
                 -
                   - /var/lib/kolla/config_files/neutron_ovs_agent.json:/var/lib/kolla/config_files/config.json:ro
                   - /var/lib/config-data/puppet-generated/neutron/:/var/lib/kolla/config_files/src:ro
+                  - /var/lib/docker-config-scripts/neutron_ovs_agent_launcher.sh:/neutron_ovs_agent_launcher.sh:ro
                   - /lib/modules:/lib/modules:ro
                   - /run/openvswitch:/run/openvswitch
             environment: