In UTM-S, all queues and all messages in these queues are preserved after the end of the application. In other words, the messages in the queues are stored safely (failsafe) and are still available after a restart. In the event of regeneration, the messages can be transferred using the KDCUPD utility.
In UTM-F, the USER and TAC queues are preserved after the end of the application, but the temporary queues are lost. The messages stored in all three types of queue are lost.
Redelivery of queue messages
If queue messages were processed and if the transaction is then rolled back, the messages are placed back in the queue. They can be read with DGET. The maximum number of redeliveries can be set at generation (REDELIVERY operand in the MAX statement). Redelivery can also be deactivated using this operand.
When the DGET call is executed, the number of redeliveries is output in the KB return area.
Alternatively, such messages can also be saved in the dead letter queue.