06F

Explanation

The system found one of the following along a path to a device:
  • An inoperative control unit
  • A channel error
  • An undetermined error

There is no device reservation or active I/O operation on the path to indicate which system owns the device.

If the system could not determine the channel path identifier and/or device number, the system substitutes X'FFFF' for the channel path identifier and/or device number.

System action

The system:
  1. Disables the device.
  2. Enters wait state X'06F' because it cannot issue message IOS427A.
  3. Expects an operator action, but does not prompt the operator for a reply.

Operator response

Do the following:
  1. Find the address of the error information by using the hardware Alter/Display facility to display the contents of location X'40C'. Record the first 4 bytes of data at this location.
  2. Use the hardware Alter/Display facility to display the storage pointed to by location X'40C'.
    Note: This is indirect addressing.
    The system displays the contents of the error information area:
    Offset 0
    The channel path identifier (or X'FFFF', if the CHPID could not be determined).
    Offset 2
    The device number (or X'FFFF', if the device number could not be determined).
  3. Use the hardware Alter/Display facility to change location X'30E' to one of the following recovery codes:
    Code
    Explanation
    00
    Try to restart the device without attempting recovery. (Entering this code is the same as replying NOOP to message IOS427A). If the problem persists, the system issues message IOS427A again (or wait state code X'06F' if the system cannot issue IOS427A); consider entering one of the other recovery codes.

    Use the Restart facility to restart the waiting processor.

    01
    Attempt to recovery access to the device through an alternate channel path. (Entering this code is the same as replying UR to message IOS427A). Before entering this recovery code and restarting the processor, all other processors that share the device you must prevent from initiating I/O to this device by issuing the IOACTION STOP command. If this command fails, you must stop all sharing processors to prevent I/O activity to the shared device.
    Use the Restart facility to restart the waiting processor. The system might issue one of the following messages:
    • IOS428I - The attempt to access the device through an alternate channel path was successful.
    • IOS104I - The attempt to access the device through an alternate channel path was not successful.

    After the system issues either message, start I/O to the shared device either by issuing the IOACTION RESUME command or by restarting the sharing processors if they were stopped in step 11.

    02
    Force the device offline. (Entering this code is the same as replying BOX to message IOS427A). The system issues message IOS501I. Use the Restart facility to restart the waiting processor.

See message IOS427A in z/OS MVS System Messages, Vol 10 (IXC-IZP) for additional information.

Source

Input/output supervisor (IOS)