Restrictions on the use of EXEC CICS commands

The commands that a node error program (NEP) can issue are restricted. In particular, do not use commands that require a principal facility, because their results are unpredictable.

Do not use commands that start the following functions:
  • Terminal control. For example, issuing an EXEC CICS DELAY command can cause the CSNE task to suspend and never resume, which can cause shutdown of the region to hang. CEMT-type commands, however, such as EXEC CICS INQUIRE TERMINAL, are permitted.
  • BMS (except routing).
  • ISC communication (including function shipping), including START requests for remote transactions, although such requests are not recommended because CSNE (Node Abnormal Condition task) might become suspended while issuing an ALLOCATE command to the remote system.

    To start a remote transaction, start a local transaction which in turn starts a remote transaction.

  • Updates to recoverable resources. If the resources are locked by another task, the CSNE unit of work can be suspended or shunted.

You cannot use the NEP to suppress DFHZNAC messages.