$ onedatastore show cephds
DATASTORE 101 INFORMATION                                                       
ID             : 101                 
NAME           : cephds              
USER           : oneadmin            
GROUP          : oneadmin            
CLUSTER        : -                   
TYPE           : IMAGE               
DS_MAD         : ceph                
TM_MAD         : ceph                
BASE PATH      : /var/lib/one//datastores/101
DISK_TYPE      : RBD        

# rados lspools
data
metadata
rbd
                            <---- ?????
.eu.rgw.root
.eu-west-1.domain.rgw
.eu-west-1.rgw.root
.eu-west-1.rgw.control
.eu-west-1.rgw.gc
.eu-west-1.rgw.buckets.index
.eu-west-1.rgw.buckets
.eu-west-1.log


# ceph osd dump | grep "pool 4 "
pool 4 '' replicated size 2 min_size 1 crush_ruleset 0 object_hash rjenkins pg_num 8 …

var cluster = new rados.Rados( "ceph", "client.admin", "/etc/ceph/ceph.conf");
cluster.connect();

var ioctx = new rados.Ioctx(cluster, "data");
ioctx.aio_write("testfile2", new Buffer("1234567879ABCD"), 14, 0, function (err) {
    if (err) {
      throw err;
    }
    ...