The CephPools parameter in the docker templates for Ceph is configured as list, as it is meant to be, but the contents are misinterpreted as strings while they should be dicts.
Moving reference to the pike backport
Build openstack-tripleo-heat-templates-7.0.3-20.el7ost includes a patch from this bug, please update BZ state accordingly
*** Bug 1534861 has been marked as a duplicate of this bug. ***
verified on openstack-tripleo-heat-templates-7.0.3-21.el7ost.noarch
Since the problem described in this bug report should be resolved in a recent advisory, it has been closed with a resolution of ERRATA. For information on the advisory, and where to find the updated files, follow the link below. If the solution does not work for you, open a new bug report. https://access.redhat.com/errata/RHBA-2018:0253