Open Stack

On 11/29/2012 06:09 PM, Brian Waldon wrote:
> On Nov 29, 2012, at 7:56 AM, Gary Kotton wrote:
>
>> Hi,
>> Due to the patch https://github.com/openstack/glance/commit/3d532de we have a problem running Quantum and Glance on devstack. This just opens a pandoras box of problems. Glance sets the queue as durable, Quantum uses the default value which is false - this causes an exception "AMQPChannelException: (406, u"PRECONDITION_FAILED - parameters for queue 'notifications.info' in vhost '/' not equivalent", (50, 10)".
>> The underlying problem is the way in which the notifications are implemented. I am not really sure if and how this can be addressed as I am not familiar with the code.
> Glance itself will default to non-durable queues (config opt rabbit_durable_queues), but there's code in Devstack that will attempt to match Glance's durability to that of an existing queue. Can you verify that the relevant code in Devstack is functioning correctly? See 'rabbit_durable_queues()' in lib/glance.

Yes, this works correctly. The problem is that Quantum works with the 
default (which is False). Hence the exception from the broker. This is 
just one problem. At the moment the Quantum DHCP agent is built upon the 
notification mechanism. If I understand correctly if Glance and Quantum 
are sending to the same queue then the listener(s) will read the 
messages in a round robin fashion. This may break the functionality of 
the DHCP agent