Comment 1 for bug 1787910

the only place i can find reference of CUSTOM_BAREMETAL is in this [1] undercloud post config bash which is called for the heat deployed undercloud. However its the overcloud deploy which fails with "ResourceInError: resources.Controller: Went to status ERROR due to "Message: No valid host was found. There are not enough hosts available., Code: 500" like [2] (and same for all the node types as you can see in [2]).

[1] https://github.com/openstack/tripleo-heat-templates/blob/46ef07433632ae5639df2e53e181ec0abd0d7b34/extraconfig/post_deploy/undercloud_post.sh#L78
[2] https://logs.rdoproject.org/openstack-periodic/git.openstack.org/openstack-infra/tripleo-ci/master/legacy-periodic-tripleo-ci-centos-7-ovb-3ctlr_1comp-featureset001-master/1544941/logs/undercloud/home/zuul/overcloud_deploy.log.txt.gz#_2018-08-20_02_03_49