Data devs are similar to SAVE devices, in that they are not visible to the hosts and must be contained in a pool before they can be used. Thin devices are bind to thin pool which contains data devices.

In your case, device id 945 is SLV just like other devices and its a logical name for your hyper on the disk.

Regards,

Saurabh

is that mean... all HDD's hypers are mapped to storage pools as a data/save devs and
on top on it a logical tdev/vdev will be created, right?

hypers that comprise TDAT reside on physical drives. Then TDATs as assigned to pools, on top of which you create TDEVs. Here is a 2-way Mirr TDAT ..as you can see it's comprised of two hypers that reside on disk 7B:D0 and 8D:C0

Back End Disk Director Information
        {
        Hyper Type                             : RAID-1
        Hyper Status                           : Ready           (RW)
        Disk [Director, Interface, TID]        : [N/A,N/A,N/A]
        Disk Director Volume Number            : N/A
        Hyper Number                           : N/A
        Mirror Number                          : 1
        Disk Group Number                      : 1
        Disk Group Name                        : DISK_GROUP_001
        }

    RAID Group Information
        {
        Mirror Number                            : 1
        RAID Type                                : RAID-1
        Device Position                          : Primary
        Protection Level                         : 2
        RAID Group Service State                 : Normal
        Failing Member Mask                      : N/A
        Hyper Devices:
            {
            Device : 00A2
                {
                ------------------------------------------------------
                 Disk     DA       Hyper       Member        Disk
                DA :IT   Vol#   Num Cap(MB)  Num Status  Grp#  Cap(MB)
                ------------------------------------------------------
                07B:D0    200     4   67603    1 RW         1   279140
                08D:C0      4     4   67603    2 RW         1   279140
                }
            }
        }