CBQE-928: fix online upgrade with port

Change-Id: Ie9b1952432188b6df7fdbb2b01a0273e12e8d652
Reviewed-on: http://review.couchbase.org/24471
Reviewed-by: Andrei Baranouski <andrei.baranouski@gmail.com>
Tested-by: Iryna Mironava <irynamironava@yandex.ru>