Enterprise storage server support

TDMF supports the IBM® Enterprise Storage Server® (ESS) Storage Controller with the Parallel Access Volume (PAV) feature.

Support for the PAV feature is in exploitation mode. This means that during the life of a TDMF migration the PAV feature is dynamically disabled and dynamically re-enabled when the migration completes for that volume only.

Before migrating data to, or establishing data on, an IBM Storage Controller (ESS) device, customers should ensure that they understand these I/O functions.

The ESS subsystem can be defined with Transparent, Toleration, or Exploitation mode.

Transparent mode
  • IODEVICE macro instruction with UNIT=3390

    If the preceding is true, then the PAV feature is not enabled. TDMF functions with no issues.

Toleration mode
  • CNTLUNIT macro instruction with UNIT=2105
  • IODEVICE macro instruction with UNIT=3390B

    If the preceding is true, TDMF migrates this volume as if it were in exploitation mode.

  • IODEVICE macro instruction with UNIT=3390A

    If the preceding is true, then the device is defined as an alias PAV volume. TDMF will not migrate these volumes.

Exploitation mode
  • CNTLUNIT macro instruction with UNIT=2105
  • IODEVICE macro instruction with UNIT=3390B

    If the preceding is true and the proper levels of MVS™ maintenance is installed, TDMF will migrate this volume as if it were in exploitation mode, and the device is eligible as a base PAV volume. TDMF supports both standard and dynamic PAVs.