Request-recovery command

Upon receipt of the VTAM® Request-Recovery (RQR) command, IMS issues a CLEAR. The SLU P application programmer must exercise care when sending this command while a recoverable IMS output message is in progress.

To send an RQR command to IMS, the application program must first respond to the output operation that is in progress. If the application program does not send the reply but instead sends only the RQR command, the controller automatically sends the outstanding DR2 reply at the LEXIT or next LREAD statement. If IMS receives the RQR command before the DR2 reply, the CLEAR generated by IMS can cause the DR2 reply to be lost. The status of the current output message is then unpredictable.

Restriction: Session initiation and resynchronization caused by an SNA Request-Recovery (RQR) command is not allowed when the node is in response mode and the response reply message is not yet available for output; that is, the input response mode transaction is still queued or in the process of execution. Response-mode transactions are not recoverable or restartable prior to the application sync point; therefore, session input acknowledgment does not occur until input processing is complete.