1. What is the problem
Shared vlan type driver has been merged, so we can run two VMs in
the same network but across two pods. However if we attach a network
to the router, the tricircle plugin still check if the network is
bound to one AZ, so one network cannot cross different pods if we
are going to attach it to a router.
2. What is the solution to the problem
The reason we require network to be bound to AZ is that when the
network is attaching the one router, we know where to create the
bottom network resources. To support l3 networking in shared vlan
network, we need to remove this restriction.
In the previous patches[1, 2], we have already move bottom router
setup to an asynchronouse job, so we just remove the AZ restriction
and make the tricircle plugin and the nova_apigw to use the job.
Floating ip association and disassociation are also moved to bottom
router setup job.
3. What the features need to be implemented to the Tricircle
to realize the solution
Now network can be attached to a router without specifying AZ, so
l3 networking can work with across-pod network.
[1] https://review.openstack.org/#/c/343568/
[2] https://review.openstack.org/#/c/345863/
Change-Id: I9aaf908a5de55575d63533f1574a0a6edb3c66b8