Open Stack

Hey all,

Part of the rollout plan for zuul v3 involves rolling out the new
zookpeer-based nodepool launchers before we roll out zuul v3 itself.
We've mostly spoken about this in a hand-wavy mannr so far, but I think
we may have a fairly simple answer of how to approach it - so I'd like
to propose the following:

* Make a branch of current nodepool master that we don't intend to merge
back ever.

* Replace the OpenStack interactions in the provider_manager with zk api
calls.

* Make a copy of our nodepool.yaml file that has min-ready set to zero
for everything.

* Run a copy of nodepool from the branch pointed at the new v3
zookeeper-based nodepool.

This should allow the shim nodepool to make real-time requests for nodes
of the new nodepool and attach them to the 2.5 ansiblelaunchers. It
makes the v3 nodepool the system of record. Once that's all in place, we
should be able to also roll out a zuul v3 installation that is also
pointed at the new nodepool, and have both shim-nodepool and zuul v3 be
clients of nodepool v3.

Once we've finished migrating to zuul v3, we'll just delete the shim server.

Sound good to everyone?

Monty