openstack team mailing list archive

[Gary Kotton <gkotton@xxxxxxxxxx>]

On 07/23/2012 11:02 AM, Dan Wendlandt wrote:
> On Sun, Jul 22, 2012 at 5:51 AM, Gary Kotton <gkotton@xxxxxxxxxx 
> <mailto:gkotton@xxxxxxxxxx>> wrote:
>
>
>
>     This is an interesting idea. In addition to the creation we will
>     also need the update. I would prefer that the agents would have
>     one topic - that is for all updates. When an agent connects to the
>     plugin it will register the type of operations that are supported
>     on the specific agent. The agent operations can be specific as bit
>     masks.
>
>     I have implemented something similar in
>     https://review.openstack.org/#/c/9591
>
>     This can certainly be improved and optimized. What are your thoughts?
>
>
> Based on your follow-up emails, I think we're now thinking similarly 
> about this.  Just to be clear though, for updates I was talking about 
> a different topic for each entity that has its own UUID (e.g., topic 
> port-update-f01c8dcb-d9c1-4bd6-9101-1924790b4b45)

Printout from the rabbit queues (this is for linux bridge where at the 
moment the port update and network deletion are of interest (unless we 
decide to change the way in which the agent is implemented))

openstack@openstack:~/devstack$ sudo rabbitmqctl list_queues
Listing queues ...
q-agent-network-update    0
q-agent-network-update.10351797001a4a231279    0
q-plugin    0
q-agent-port-update.10351797001a4a231279    0

10351797001a4a231279 == IP and MAC of the host

>     In addition to this we have a number of issues where the plugin
>     does not expose the information via the standard API's - for
>     example the VLAN tag (this is being addressed via extensions in
>     the provider networks feature)
>
>
> Agreed.  There are a couple options here: direct DB access (no 
> polling, just direct fetching), admin API extensions, or custom RPC 
> calls.  Each has pluses and minuses.  Perhaps my real goal here would 
> be better described as "if there's an existing plugin agnostic way to 
> doing X, our strong bias should be to use it until presented with 
> concrete  evidence to the contrary".   For example, should a DHCP 
> client create a port for the DHCP server via the standard API, or via 
> a custom API or direct DB access?  My strong bias would be toward 
> using the standard API.

Good question. I think that if the standard API's can be used then we 
should go for it. Problem is that these require additional configurations.

>     3. Logging. At the moment the agents do not have a decent logging
>     mechanism. This makes debugging the RPC code terribly difficult.
>     This was scheduled for F-3. I'll be happy to add this if there are
>     no objections.
>
>
> That sounds valuable.

Hopefully I'll be able to find some time for this.
>     4. We need to discuss the notifications that Yong added and how
>     these two methods can interact together. More specifically I think
>     that we need to address the configuration files.
>
>
> Agreed.  I think we need to decide on this at monday's IRC meeting, so 
> we can move forward.  Given F-3 deadlines, I'm well aware that I'll 
> have to be pragmatic here :)
>
>
>     The RPC code requires that the eventlet monkey patch be set. This
>     cause havoc when I was using the events from pyudev for new device
>     creation. At the moment I have moved the event driven support to
>     polling (if anyone who reads this is familiar with the issue or
>     has an idea on how to address it any help will be great)
>
>
> Sorry, wish I could help, but I'm probably in the same boat as you on 
> this one.

I have a solution that works. In the long term it would be better if 
this was event driven. This all depends on how the discussions above 
play out.
> I'm going to make sure we have a good chunk of time to discuss this 
> during the IRC meeting on monday (sorry, I know that's late night for 
> you...).

:). Tomorrow is jet lag day!
> Dan
>
>
>
>     Thanks
>     Gary
>
> >     Dan
> >
> >
> >     ~~~~~~~~~~~~~~~~~~~~~~~~~~~
> >     Dan Wendlandt
> >     Nicira, Inc: www.nicira.com <http://www.nicira.com>
> >     twitter: danwendlandt
> >     ~~~~~~~~~~~~~~~~~~~~~~~~~~~
>
>
>
>
> --
> ~~~~~~~~~~~~~~~~~~~~~~~~~~~
> Dan Wendlandt
> Nicira, Inc: www.nicira.com <http://www.nicira.com>
> twitter: danwendlandt
> ~~~~~~~~~~~~~~~~~~~~~~~~~~~