Description of problem: trove-* services (on the host) do not start if the underlying database (sql_connect), which means mariadb for RHEL-OSP, is not running. I opened an more general upstream bug (see the related External Bug) about trove services being able to start in such scenario, but I suspect it would take time and it could be marked as expected behavior. Adding a dependency on the mariadb unit from the trove-* ones should easily fix this problem. Version-Release number of selected component (if applicable): openstack-trove-2014.2.2-1.el7ost
The fix was applied to openstack-trove-guestagent, which - if I understand it correctly - could be executed on a image without mysql. On the other side, the fix is needed by the services running on the Trove host (api, conductor, taskmanager).
Updated thanks to Pete & Luigi feedback
The dependency has been introduced for the 3 services (systemd units). Verified on latest RHEL7.1, with: openstack-trove-api-2014.2.3-3.el7ost.noarch openstack-trove-taskmanager-2014.2.3-3.el7ost.noarch openstack-trove-conductor-2014.2.3-3.el7ost.noarch This also means that, until the upstream problem is solved, Trove services must be installed on the node running mariadb. This should go into release notes or also other documentation with known limitations.
As for my comment in #6, now Trove services must be installed on the same node where mariadb is running. This is a workaround because Trove services unfortunately do not start when the database can't be reached, but the database can be remote. Should this be documented simply in the Doc Text (-> errata doc), or should it go into some other document as well?
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://rhn.redhat.com/errata/RHBA-2015-0928.html
Regarding comment #7, raised docs bug for the Trove MariaDB dependency: BZ#1220630.