Comment 9 for bug 1981634

During overcloud deployment ...
1. tripleo_run_cephadm is run by config-download [1] and logs to ~/ansible.log
2. tripleo_cephadm is run in a nested ansible [1] and logs to ~/config-download/<stack>/cephadm/cephadm_command.log
3. tripleo_ceph_client is run by config-download [1] and logs to ~/ansible.log

The FSID and MonIPs are exported by role tripleo_cephadm [2] (during step 2 above)
The FSID and MonIPs are imported by role tripleo_ceph_client [3] (during step 3 above)
Thus, both deploy_steps and external_deploy_steps MUST reference the same tripleo_ceph_client_vars path
However, {{ playbook_dir }} is not the same path in both 1 and 2
Everything was fine until [4] which wasn't really necessary because of [5]

[1] https://docs.openstack.org/project-deploy-guide/tripleo-docs/latest/deployment/ansible_config_download.html#deploy-steps-playbook-yaml

[2] https://github.com/openstack/tripleo-ansible/blob/master/tripleo_ansible/roles/tripleo_cephadm/tasks/export.yaml#L86

[3] https://github.com/openstack/tripleo-ansible/blob/master/tripleo_ansible/roles/tripleo_ceph_client/tasks/main.yml#L32-L34

[4] https://github.com/openstack/tripleo-ansible/commit/93cc215909db617aece85cb53c0279d04c04c69a
[5] https://github.com/openstack/python-tripleoclient/commit/fda3233451db678642fd57f920487db7ca63dc30