Comment 66 for bug 1661134

Reviewed: https://review.opencontrail.org/34424
Committed: http://github.com/Juniper/contrail-controller/commit/4dedf42052ed5fad6d9cdbc6d936219efa6ee323
Submitter: Zuul (<email address hidden>)
Branch: R3.2

commit 4dedf42052ed5fad6d9cdbc6d936219efa6ee323
Author: Sachin Bansal <email address hidden>
Date: Sun Jul 30 13:24:41 2017 -0700

Do not generate vrf assign rules for book-end RIs

When one port of a service VM is used in multiple service instances, the VRF
assign rules generated for this interface cannot identify which of those VRF
to use for the traffic. This is because VRF assign rules currently don't have
src or dst VN information. With this change, we will not create VRF assign
rules for 'book-end' interfaces, i.e., the left interface of the first instance
and right interface in the last instance in the chain. This allows us to
support this case when such a shared interface is the first or last in the
service chain.

Change-Id: Ibe9882fa96d4279b67c9aea469445c358505d957
Closes-Bug: 1661134
(cherry picked from commit 7604a7a845c9c0b029dc8ac478af864d1fbc52f4)