Description of problem: https://access.redhat.com/documentation/en-us/red_hat_ceph_storage/3/html-single/installation_guide_for_red_hat_enterprise_linux/index#installing-metadata-servers Section 3.4. Installing Metadata Servers states: Run the Ansible playbook: [user@admin ceph-ansible]$ ansible-playbook site-docker.yml --limit mdss This should say: Run the Ansible playbook: [user@admin ceph-ansible]$ ansible-playbook site.yml --limit mdss Version-Release number of selected component (if applicable): Latest