[Rdo-list] Neutron-openswitch-agent configuration workaround in RDO Juno/Kilo and now in Liberty

[Ihar Hrachyshka]

Markelov Andrey <amarkelov at yandex.ru> wrote:

> Hi guys,
>
> If we will see at Juno and Kilo installation guide for CentOS at  
> docs.openstack.org we can see documented workaround about   
> /etc/neutron/plugin.ini (symbolic link to ml2_conf.ini) . We need to edit  
> start script for openswitch-agent as documented.

Please report the bug against upstream docs, OVS agent should NOT read from  
plugin.ini or ml2_conf.ini. What it reads is merely openvswitch_agent.ini.  
I thought it was made clear enough once we renamed ovs_neutron_plugin.ini  
into openvswitch_agent.ini in Liberty, but apparently upstream docs team  
still assumes plugin.ini is meant to be read by the agent.

The fact that devstack still (wrongfully) configures the agent with  
ml2_conf.ini does not help to clarify the intended setup either:

https://github.com/openstack-dev/devstack/blob/master/lib/neutron_plugins/openvswitch_agent#L52

Can you btw provide a link to Liberty docs where it’s documented?

>
> With Liberty that workaround does not works because  
> /usr/lib/systemd/system/neutron-openvswitch-agent.service was changed.  
> “Any” plugin.ini now not in –config-file options for Openswitch-agent.
>
> And it not documented in Liberty install guide.
>
> As solution you can rename /etc/neutron.plugins/ml2_conf.ini to  
> /etc/neutron.plugins/openswitch_agent.ini and it will work.

The proper solution is to stop configuring the agent using either  
ml2_conf.ini or plugin.ini, and instead put all agent configuration into  
openvswitch_agent.ini.

> Time by time I lead OpenStack Training cources and I want to explain  
> config files and procidures in “right way”.
>
> My questions are
> What the idea behind deleting plugin.ini from –config-file options?

Because so called core plugins (ml2, ovn, …) are neutron-server only  
thingies. They have nothing to do on agent side.

> Is the ml2_conf.ini obsolete?

It is not obsolete. It is still used by neutron-server (thru plugin.ini  
symlink) in case ml2 is the core plugin for the setup.

> Is the plugin.ini obsolete?
>

No, it’s not obsolete. It is still used by neutron-server to get access to  
core plugin specific configuration (f.e. [ml2] section from ml2_conf.ini).

I hope it clarifies the matter.

Ihar