Synchronizing three or more CICS systems

This section gives examples of how to commit and back out recoverable resources affected by three or more DTP transactions connected on conversations at sync level 2.

Note: Session failure and the indoubt period

During the period between the sending of the syncpoint request to the partner region and the receipt of the reply, the local region does not know whether the partner region has committed the change. This is known as the indoubt period. If the intersystem session fails during this period, the local CICS® system cannot tell whether the partner region has committed or backed out its resource changes. This situation could occur for situations other than DTP and is discussed in Recovery functions and interfaces.