DFS1252I I/O ERROR ON REFERAL, SNAP ID=124 TAKEN.

Explanation
An I/O error has occurred on the REFERAL library. A SNAP dump has been
taken to the SYSSNAP DD data set.

System action
Processing continues with the next source statement.

Programmer response
Determine the cause of the I/O error, correct the error, and resubmit the
job.