Move Medium - X'A5'

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Table 1 shows the format of the Move Medium command.

Table 1. Move Medium Command
Byte Bit 7
MSB		 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
LSB
0 Operation code (X'A5')
1 LUN (Obsolete) Reserved
2 Transport Element Address
3
4 Source Address
5
6 Destination Address
7
8 Reserved
9 Reserved
10 Reserved Invert (B'0')
11 HD control Reserved (B'0000') Flag (B'0') Link (B'0')
  • Transport Element Address: For any of these values, the library selects an MTE based on optimal availability and performance. The following values apply:
      X'0000'  
      X'0001'  
      X'0002'
  • Source/Destination Addresses: The valid element addresses for these fields depend on the library's configuration. (See SCSI element addresses.)
    Notes:
    1. The Medium Transport Element is not capable of storing a media element. If this element address is specified as a Destination Address in a Move Medium command, the command is presented CHECK CONDITION status with associated sense data of 5/2101 (Illegal Request, Invalid Element Address).
    2. If the source element address contains a cartridge that is assigned to another logical library (for example, exported to the shared I/O station), the command is presented CHECK CONDITION status with associated sense data of 5/3B81 (Illegal Request, Element Not Accessible, Cartridge is Assigned to Another Logical Library).
  • HD Control: The following values apply:
    B'00' Default behavior (Cache optimized)
    B'01' Ignored for all moves
    B'10' No unshuffle (Does not unshuffle cartridges that are shuffled out of a slot.)
    B'11' Optimized empty/fill sequence. (When the Source Move Element is a drive, the preferred destination is an empty UHD slot. Once selected, that UHD slot is then selected as the destination in successive usages of this option until the once-empty UHD slot is full. Usage of this option requires frame/column/row/tier awareness for cartridges being moved to drives in order to create the empty UHD slots.)
     
    Note:

    The depth of a cartridge location in a UHD slot is known as a tier. The cartridge immediately accessible in a UHD slot is a Tier 1 cartridge. Behind that is Tier 2, and so on. The maximum tier in an LTO UHD slot is Tier 9.

    A shuffle operation is required to access any cartridge in Tier 2 or beyond. A shuffle is the process of moving cartridges in lower tiers into the gripper or other available slots to access cartridges in higher tiers. Tier 2 cartridges require a swap only by using the dual grippers (assuming both grippers are usable).

    Drive-to-storage or storage-to-storage moves have the same effect as updating the cartridge "usage" date and time for consideration in subsequent LRU (Least Recently Used) cache destage operations. Hence, an application does not need awareness of the physical locations of cartridges to prepare a set of cartridges for faster future access. The application needs to send storage-to-storage moves only for the entire set of cartridges.

For additional information on element addresses and descriptions, refer to the following sections: