Migrating Pike overcloud to containerized overcloud failed due to DBConnectionError

[Artem Hrechanychenko]

Description
===========
I am tried to migrate fresh build of Pike deployed by tripleo-quickstart to containers using https://etherpad.openstack.org/p/pike-tripleo-upgrades and retrieve error:http://pastebin.test.redhat.com/473598

Steps to reproduce
==================
1.Deploy undercloud + Overcloud(1 controller + 1 compute) using tripleo-quickstart
2.follow https://etherpad.openstack.org/p/pike-tripleo-upgrades

Expected result
===============
stack updated successfully and all services moved to docker containers

Actual result
=============
stack update failed

Environment
===========
1. Openstack Pike
Logs & Configs
==============

rpm -qa |grep docker
python-docker-pycreds-1.10.6-1.el7.noarch
docker-distribution-2.6.0-1.el7.x86_64
docker-1.12.6-11.el7.centos.x86_64
docker-client-1.12.6-11.el7.centos.x86_64
python-heat-agent-docker-cmd-1.0.1-0.20170403171714.251d7ab.el7.centos.noarch
python-docker-py-1.10.6-1.el7.noarch
docker-common-1.12.6-11.el7.centos.x86_64

http://pastebin.test.redhat.com/473602

[Emilien Macchi (emilienm)]

Setting to low because people are still working on this "feature" now, so I don't consider it as a bug really, as we don't support the feature yet. But keeping it for record is nice, so we can track the work that is done to solve this challenge, thanks for reporting it!