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No worries, happy to share. Answers below.

Michael


On Tue, Jul 31, 2018 at 9:49 PM Flint WALRUS <gael.therond at gmail.com> wrote:
>
> Hi Michael,
>
> Oh ok! That config-drive trick was the missing part! Thanks a lot! Is there a release target for the API vs config-drive thing? I’ll have a look at an instance as soon as I’ll be able to log into one of my amphora.

No I have no timeline for the amphora-agent config update API.  Either
way, the initial config will be installed via config drive. The API is
intended for runtime updates.
>
> By the way, three sub-questions remains:
>
> 1°/ - What is the best place to push some documentation improvement ?

Patches are welcome!  All of our documentation is included in the
source code repository here:
https://github.com/openstack/octavia/tree/master/doc/source

Our patches follow the normal OpenStack gerrit review process
(OpenStack does not use pull requests).

> 2°/ - Is the amphora-agent an auto-generated file at image build time or do I need to create one and give it to the diskimage-builder process?

The amphora-agent code itself is installed automatically with the
diskimage-builder process via the "amphora-agent" element.
The amphora-agent configuration file is only installed at amphora boot
time by nova using the config drive capability. It is also
auto-generated by the controller.

> 3°/ - The amphora agent source-code is available at https://github.com/openstack/octavia/tree/master/octavia/amphorae/backends/agent isn’t?

Yes, the agent code that runs in the amphora instance is all under
https://github.com/openstack/octavia/tree/master/octavia/amphorae/backends
in the main octavia repository.

>
> Sorry for the questions volume, but I prefer to really understand the underlying mechanisms before we goes live with the solution.
>
> G.
>
> Le mer. 1 août 2018 à 02:36, Michael Johnson <johnsomor at gmail.com> a écrit :
>>
>> Hi Flint,
>>
>> Happy to help.
>>
>> Right now the list of controller endpoints is pushed at boot time and
>> loaded into the amphora via config drive/nova.
>> In the future we plan to be able to update this list via the amphora
>> API, but it has not been developed yet.
>>
>> I am pretty sure centos is getting the config file as our gate job
>> that runs with centos 7 amphora has been passing. It should be in the
>> same /etc/octavia/amphora-agent.conf location as the ubuntu based
>> amphora.
>>
>> Michael
>>
>>
>>
>> On Tue, Jul 31, 2018 at 10:05 AM Flint WALRUS <gael.therond at gmail.com> wrote:
>> >
>> > Hi Michael, thanks a lot for that explanation, it’s actually how I envisioned the flow.
>> >
>> > I’ll have to produce a diagram for my peers understanding, I maybe can share it with you.
>> >
>> > There is still one point that seems to be a little bit odd to me.
>> >
>> > How the amphora agent know where to find out the healthManagers and worker services? Is that because the worker is sending the agent some catalog informations or because we set that at diskimage-create time?
>> >
>> > If so, I think the Centos based amphora is missing the agent.conf because currently my vms doesn’t have any.
>> >
>> > Once again thanks for your help!
>> > Le mar. 31 juil. 2018 à 18:15, Michael Johnson <johnsomor at gmail.com> a écrit :
>> >>
>> >> Hi Flint,
>> >>
>> >> We don't have a logical network diagram at this time (it's still on
>> >> the to-do list), but I can talk you through it.
>> >>
>> >> The Octavia worker, health manager, and housekeeping need to be able
>> >> to reach the amphora (service VM at this point) over the lb-mgmt-net
>> >> on TCP 9443. It knows the amphora IP addresses on the lb-mgmt-net via
>> >> the database and the information we save from the compute driver (I.e.
>> >> what IP was assigned to the instance).
>> >>
>> >> The Octavia API process does not need to be connected to the
>> >> lb-mgmt-net at this time. It only connects the the messaging bus and
>> >> the Octavia database. Provider drivers may have other connectivity
>> >> requirements for the Octavia API.
>> >>
>> >> The amphorae also send UDP packets back to the health manager on port
>> >> 5555. This is the heartbeat packet from the amphora. It contains the
>> >> health and statistics from that amphora. It know it's list of health
>> >> manager endpoints from the configuration file
>> >> "controller_ip_port_list"
>> >> (https://docs.openstack.org/octavia/latest/configuration/configref.html#health_manager.controller_ip_port_list).
>> >> Each amphora will rotate through that list of endpoints to reduce the
>> >> chance of a network split impacting the heartbeat messages.
>> >>
>> >> This is the only traffic that passed over this network. All of it is
>> >> IP based and can be routed (it does not require L2 connectivity).
>> >>
>> >> Michael
>> >>
>> >> On Tue, Jul 31, 2018 at 2:00 AM Flint WALRUS <gael.therond at gmail.com> wrote:
>> >> >
>> >> > Hi Folks,
>> >> >
>> >> > I'm currently deploying the Octavia component into our testing environment which is based on KOLLA.
>> >> >
>> >> > So far I'm quite enjoying it as it is pretty much straight forward (Except for some documentation pitfalls), but I'm now facing a weird and hard to debug situation.
>> >> >
>> >> > I actually have a hard time to understand how Amphora are communicating back and forth with the Control Plan components.
>> >> >
>> >> > From my understanding, as soon as I create a new LB, the Control Plan is spawning an instance using the configured Octavia Flavor and Image type, attach it to the LB-MGMT-NET and to the user provided subnet.
>> >> >
>> >> > What I think I'm misunderstanding is the discussion that follows between the amphora and the different components such as the HealthManager/HouseKeeper, the API and the Worker.
>> >> >
>> >> > How is the amphora agent able to found my control plan? Is the HealthManager or the Octavia Worker initiating the communication to the Amphora on port 9443 and so give the agent the API/Control plan internalURL?
>> >> >
>> >> > If anyone have a diagram of the workflow I would be more than happy ^^
>> >> >
>> >> > Thanks a lot in advance to anyone willing to help :D
>> >> >
>> >> > _______________________________________________
>> >> > OpenStack-operators mailing list
>> >> > OpenStack-operators at lists.openstack.org
>> >> > http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack-operators