ceph-ansible/roles/ceph-restapi/tasks/start_restapi.yml

---
- name: check if Ceph REST API is already started
  shell: "pgrep ceph-rest-api"
  ignore_errors: true
  register: restapi_status

- name: start Ceph REST API
  shell: "nohup ceph-rest-api &"
  changed_when: false
  when: restapi_status.rc != 0