112

Explanation

The system detected a hot I/O condition on a reserved direct access storage device (DASD).

System action

The system leaves the device status pending and issues message IOS112D. Depending on the recovery code entered by the operator, one of the following:
Code
Response
01
The system clears the device status. The device remains online. The system does not attempt channel path recovery. Processing continues.
02 or 03
The system boxes the device:
  • The I/O on the device is ended.
  • Any new I/O requests result in permanent I/O errors.
  • The system does not perform new allocations for the device.
  • If the device was online, the system marks it pending offline. A pending offline device goes offline when the following conditions occur, in this order:
    1. The device is no longer allocated to any job.
    2. Allocation processing allocates any device in the system.
  • If the device was offline, it remains offline.
04
The system tries to recover the channel path. If channel path recovery is successful, the system:
  • Issues message IOS203I
  • Leaves the channel path online
  • Clears the pending status of the hot device
If channel path recovery is not successful, the system issues message IOS202I and forces the channel path offline.
05
The system forces the channel path offline. The system issues message IOS202I.
06
The system tries to recover the control unit. If recovery is successful, the system:
  • Issues message IOS208I
  • Leaves the device paths online for all devices on the same control unit
  • Clears the pending status of the cleared device
If recovery is not successful, the system issues message IOS207I.

Operator response

Do the following:
  1. Find the address of the status collection data (SCD) area 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'.
  3. Contact hardware support.
  4. Use the hardware Alter/Display facility to change location X'30E' to one of the following recovery codes:
    Code
    Explanation
    01
    Do not attempt channel path recovery.
    02
    Box the device.
    03
    Allow the operator to store the device number of each device on the control unit in the operator reply area for IOS110D.
    04
    Try to recover the channel path.
    05
    Force the channel path offline.
    06
    Try to recover the control unit.
  5. Use the Restart facility to restart the waiting processor

Source

Input/output supervisor (IOS)