roles:
- [mon.a, mon.c, osd.0, osd.1, osd.2, mds.b-s-a]
- [mon.b, mgr.x, mds.a, osd.3, osd.4, osd.5, client.0]
openstack:
- volumes: # attached to each instance
    count: 3
    size: 10 # GB
log-rotate:
  ceph-mds: 10G
  ceph-osd: 10G