Permanent error condition

A permanent error condition, whether expected following a Reset to a channel path in an ending condition or unexpected, results in the system taking that channel path offline. Any active I/O requests are retried on alternate paths if available. If the failing channel path was the last path to any devices, those devices are boxed. Boxing means:
  • The operating system ends I/O to the device.
  • Any new I/O request for the device causes a permanent I/O error.
  • The operating system does not allocate the device.
  • If the device was online, the operating system marks it pending offline. A pending offline device goes offline when the following occur, in this order:
    1. The device becomes no longer allocated to any job.
    2. The operating system allocates any device.

If the device was offline, it remains offline.