Floating IPs are allocated using the wrong router ID

[Thomas Bachman]

Setup:

* a single L3P
* The L3P has two L2Ps
* each L2P has a PTG
* The L3P is connected to two external segments
* Each external segment has its own NAT pool

A network service policy for NAT was created, such that floating IPs would be allocated to instances in each PTG from each external segment.

It was observed that floating IPs would be allocated using the correct NAT pools, but the floating IPs had the same router ID:

http://pastebin.com/8JfsEhx4

The problem is here:
https://github.com/openstack/group-based-policy/blob/master/gbpservice/neutron/services/grouppolicy/drivers/resource_mapping.py#L1076-L1079

The code needs to return the router ID that is connected to the external network that matches the external network for the external segment that the NAT pool is associated with.

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: stable/mitaka
Review: https://review.openstack.org/426252

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/425987
Committed: https://git.openstack.org/cgit/openstack/group-based-policy/commit/?id=791e9f18ca297b4c2cb165b88a1a5b4a22814226
Submitter: Jenkins
Branch: master

commit 791e9f18ca297b4c2cb165b88a1a5b4a22814226
Author: Thomas Bachman <email address hidden>
Date: Fri Jan 27 00:04:37 2017 +0000

    Fix incorrect router ID in floating IP

    The APIC mapping driver with the resource mapping driver
    was always returning the same router ID if multiple floating
    IPs were allocated from different NAT pools across multiple
    external segments. When the NAT pools are from different external
    segments, then the router IDs in the floating IPs should be different.

    Change-Id: I25df94bd1c040197203bfe07c32207b9b83ee8b9
    Closes-bug: #1659609

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/426252
Committed: https://git.openstack.org/cgit/openstack/group-based-policy/commit/?id=eccd0ca6ba4b16559e181ccb50077b8d0f6b63a1
Submitter: Jenkins
Branch: stable/mitaka

commit eccd0ca6ba4b16559e181ccb50077b8d0f6b63a1
Author: Thomas Bachman <email address hidden>
Date: Fri Jan 27 00:04:37 2017 +0000

    Fix incorrect router ID in floating IP

    The APIC mapping driver with the resource mapping driver
    was always returning the same router ID if multiple floating
    IPs were allocated from different NAT pools across multiple
    external segments. When the NAT pools are from different external
    segments, then the router IDs in the floating IPs should be different.

    Change-Id: I25df94bd1c040197203bfe07c32207b9b83ee8b9
    Closes-bug: #1659609

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: stable/liberty
Review: https://review.openstack.org/426340

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/426340
Committed: https://git.openstack.org/cgit/openstack/group-based-policy/commit/?id=2ee88b891f3376053fbdd262c75f19ec52220907
Submitter: Jenkins
Branch: stable/liberty

commit 2ee88b891f3376053fbdd262c75f19ec52220907
Author: Thomas Bachman <email address hidden>
Date: Fri Jan 27 00:04:37 2017 +0000

    Fix incorrect router ID in floating IP

    The APIC mapping driver with the resource mapping driver
    was always returning the same router ID if multiple floating
    IPs were allocated from different NAT pools across multiple
    external segments. When the NAT pools are from different external
    segments, then the router IDs in the floating IPs should be different.

    Change-Id: I25df94bd1c040197203bfe07c32207b9b83ee8b9
    Closes-bug: #1659609
    (cherry picked from commit eccd0ca6ba4b16559e181ccb50077b8d0f6b63a1)