Comment 50 for bug 1721416

Reviewed: https://review.opencontrail.org/38653
Committed: http://github.com/Juniper/contrail-controller/commit/dbed80635acc489ddf1f0b0ae2597d62bd24074e
Submitter: Zuul (<email address hidden>)
Branch: R4.0

commit dbed80635acc489ddf1f0b0ae2597d62bd24074e
Author: Megh Bhatt <email address hidden>
Date: Fri Sep 29 15:04:04 2017 -0700

Maintain zookeeper lock during the whole database initialization

To ensure cassandra schema consistency, zookeeper lock is
used so that only one collector node is creating schema at
any given point of time. However if the creation of schema
fails then we were releasing the zookeeper lock and retrying.
This resulted in a situation where from cassandra perspective
schema was created concurrently and caused column family ID
mismatch. So now we will only release the zookeeper lock when
the schema creation is successful.

Change-Id: I887db5a5ca4d2c8b40b5c50079ed005c3f4f4b4c
Partial-Bug: #1721416