overlapping IPv6 cidrs leads to a masking failure in auto_allocate extension

[Armando Migliaccio]

Preconditions:

1) one default, external network with cidr: 2001:db8::/64
2) one default, subnet pool with cidr: 2001:db8::/64

Steps to repro:

1) neutron auto-allocated-topology-show

Actual output:

Router b1ecf10a-49f9-439e-9c8c-c8f22665b950 has no interface on subnet 7c4f7247-87b7-4ca9-a157-e508c52ee88b

Expected output:

Deployment error: Unable to provide external connectivity.

The log should be revealing as to why this configuration error led to this failure mode.

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/279837

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/279837
Committed: https://git.openstack.org/cgit/openstack/neutron/commit/?id=3785dc31a465e0ac9d5de23339daddfbc346ef7c
Submitter: Jenkins
Branch: master

commit 3785dc31a465e0ac9d5de23339daddfbc346ef7c
Author: Armando Migliaccio <email address hidden>
Date: Fri Feb 12 16:46:13 2016 -0800

    Address masking issue during auto-allocation failure

    If an interface could not successfully be plugged to a router
    during the provisioning of external connectivity, a failure
    is triggered, and a subsequent cleanup performed.

    This patch ensures that the cleanup accounts only for the
    subnets that were uplinked successfully, thus fixing the
    incomplete cleanup, and the masking user error that resulted
    otherwise.

    Closes-bug: #1545210

    Change-Id: I061a1407abf6ed1a39056b1f72fd039919e2fc79