006

Explanation
During initial program load (IPL), an I/O error
occurred while IPL was reading from the SYSRES or IODF volume. The
error can be one or more of the following: An interface control check
A channel control check
A channel data check
A program check
A channel chaining check
STATE CHANGE INTERRUPT detected due to SETCACHE SUBSYS OFF issued
on sharing system.

Note: One commonly seen cause for this problem is having
the nucleus in secondary extents. This problem has also been caused
by the nucleus containing a not-executable SVC. Browse SYS1.NUCLEUS
for any member with an attribute of NX. 

System action
The system enters a non-restartable wait state.

Operator response
Use the hardware Problem Determination facilities
to see if any errors occurred during the IPL process.  If channel
errors occurred, try configuring the channel paths offline and reipling
the system.
If the problem recurs, notify the system programmer.
If
the system programmer requests, obtain a standalone dump.

System programmer response
Search problem reporting databases
for a fix for the problem. If no fix exists, contact the IBM® Support Center. Provide the stand-alone dump.

Source
Initial program load (IPL)