MB-100: fix ns_server point for MB-8938

Change-Id: I6febc29bb4c1eb4d9df74e2072b8e923bb488a1f
Reviewed-on: http://review.couchbase.org/28638
Reviewed-by: Junyi Xie <junyi.couchbase@gmail.com>
Tested-by: Junyi Xie <junyi.couchbase@gmail.com>