Multiple API managers don't work with NSX v3 plugin

[Boden R]

Historically the NSX neutron plugins have supported multiple backend API managers. This provides additional LB and HA characteristics which our customers have become accustom to.

The NSX v3 plugin does not support multiple managers -- it only supports a single manager.

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/241796
Committed: https://git.openstack.org/cgit/openstack/vmware-nsx/commit/?id=16b105f7f533e99030a93bdef85b90b143904bb3
Submitter: Jenkins
Branch: master

commit 16b105f7f533e99030a93bdef85b90b143904bb3
Author: Boden R <email address hidden>
Date: Wed Nov 4 15:41:44 2015 -0700

    NSX v3 multi-manager

    This patch adds multi-manager support to the
    NSX v3 plugin thereby enabling the ability to specify multiple
    NSX managers for the v3 plugin.

    This implementation supports the same basic features
    as the MH multi-manager support does including;
    timeouts, retries, keep-alive, etc..

    The approach in a nutshell is to introduce a "proxy"
    class which looks like a requests or requests.Session
    object and can be used in place of requests in the
    NSX REST API client. Under the covers this class handles
    management of endpoint selection and connectivity.

    Also note that with this patch your devstack local rc / conf
    no longer needs to specify NSX_CONTROLLERS when using
    the v3 plugin. Instead a comma list of managers is supported
    on the NSX_MANAGERS devstack var.

    Closes-Bug: #1524046

    Change-Id: I433a4b9ea73de0680d64d86e2f826c092adfba87

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: stable/liberty
Review: https://review.openstack.org/255567

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/255567
Committed: https://git.openstack.org/cgit/openstack/vmware-nsx/commit/?id=a5522f6b68c26948988957872c9dfbb18e570551
Submitter: Jenkins
Branch: stable/liberty

commit a5522f6b68c26948988957872c9dfbb18e570551
Author: Boden R <email address hidden>
Date: Wed Nov 4 15:41:44 2015 -0700

    NSX v3 multi-manager

    This patch adds multi-manager support to the
    NSX v3 plugin thereby enabling the ability to specify multiple
    NSX managers for the v3 plugin.

    This implementation supports the same basic features
    as the MH multi-manager support does including;
    timeouts, retries, keep-alive, etc..

    The approach in a nutshell is to introduce a "proxy"
    class which looks like a requests or requests.Session
    object and can be used in place of requests in the
    NSX REST API client. Under the covers this class handles
    management of endpoint selection and connectivity.

    Also note that with this patch your devstack local rc / conf
    no longer needs to specify NSX_CONTROLLERS when using
    the v3 plugin. Instead a comma list of managers is supported
    on the NSX_MANAGERS devstack var.

    Closes-Bug: #1524046

    Change-Id: I433a4b9ea73de0680d64d86e2f826c092adfba87
    (cherry picked from commit 16b105f7f533e99030a93bdef85b90b143904bb3)