Optional parameters

OPENDVCS

Specifies whether Open System (fixed block) devices or CKD devices are addressed in the required parameters of this command. The values are:

NO: The required parameters address CKD devices. This is the default.
YES: Specifies that the required parameters in this command support open device management through a CKD access device.

SUBCHSET

Specifies the subchannel set in which the command is to be issued. The subchannel set where the I/O will be issued is the subchannel set as defined in the Hardware Configuration Dialog (HCD). The valid values are determined by what is supported by the host system's processor and configured for the device.

If you omit the parameter, the command is issued to the device that is logically in subchannel set 0. If a swap has occurred, this could be the device that was defined in an alternate subchannel set in the I/O configuration (IODF), with HCD.