DITTO is used to recover a logical volume from an exported stacked volume in situations where no VTS is available. DITTO does not go through OPEN processing nor issue regular mount messages. DITTO recovers the logical volume as a physical volume. As a result, managing these recovered logical volumes requires some additional consideration and processing.

Here are some considerations:

• When you specify DFSMSrmm EDGRMMxx REJECT command values to manage volumes, DFSMSrmm relies on information available at OPEN. These REJECT command values do not apply because DITTO does not issue OPEN requests.
  Note: If you use REJECT commands, you have to convert from the use of REJECT commands in order to use the PRTITION and OPENRULE commands. See Converting REJECT commands to PRTITION and OPENRULE commands for information about converting from the use of REJECT commands.
• DFSMSrmm does not update existing volume information when DITTO copies the data.
• The DITTO output volume is a physical volume but might have the same volume serial number as the original logical volume. If you use the original logical volume serial number for the recovered volume, you can convert the logical volume in the DFSMSrmm control data set to a physical volume by issuing the DFSMSrmm CHANGEVOLUME subcommand as shown in Figure 1
  Figure 1. Converting A logical volume to a physical volume

  RMM CHANGEVOLUME volser TYPE(PHYSICAL) CONTAINER(' ')-
  LOCATION(SHELF) CONFIRMMOVE FORCE

  Use the recovered volume as a normal physical volume. If the output volume serial number is different from the original logical volume serial number , the volume information, the data set information and other details can be reused by issuing the DFSMSrmm CHANGEVOLUME subcommand as shown in Figure 2.

  Figure 2. Reusing volume information for a recovered volume

  RMM CHANGEVOLUME volser TYPE(PHYSICAL) CONTAINER(' ')-
  LOCATION(SHELF) CONFIRMMOVE NEWVOLUME(pvolser)

• You can also add data set information for the DITTO output volume from the original logical volume.

  To copy details for the original logical volume to the new physical volumes, use DFSMSrmm subcommands to obtain the data set and volume details for the volumes you want to redefine.