Taskmanager "prepare" message is lost if guestagent doesn't create a queue on time

[Sergey Gotliv]

It seems like there is a race in the instance creating process.

1. Taskmanager is sending request to Nova to create a VM instance.
2. Right after Nova's response, taskmanager sending "prepare" message to the guestagent.{guest_id} queue.

Meantime in parallel between steps 1 and 2, Trove guest agent is booting and creating a queue I mentioned above.

The problem is that if taskmanager(publisher) sent a "prepare" before quest(consumer) created a queue then this message may be lost depends on the message broker.

For example, according to RabbitMQ dosumentation:

"Next, before sending we need to make sure the recipient queue exists. If we send a message to non-existing location, RabbitMQ will just trash the message."

[Amrith Kumar (amrith)]

Updating importance to "Medium" (bugscrub, 2014-10-23)

[Sushil Kumar (sushil-kumar2)]

https://github.com/openstack/trove/blob/master/trove/guestagent/api.py#L233 shows that prepare method is call with _cast_with_consumer which creates a new queue first and then passes the message, so there is not left a chance of putting a message to a non-existent queue.

[Amrith Kumar (amrith)]

This is most likely a duplicate of 1511623. The stated circumstances in this bug have not occurred in a long time and this bug has not been updated either.

I'm marking it as such.

[Launchpad Janitor (janitor)]

[Expired for OpenStack DBaaS (Trove) because there has been no activity for 60 days.]