1.3.1.1.2 Transaction Recovery

The following sequence is a schematic of the interactions that take place between the various software components involved in the usage scenario when an XA Transaction Manager comes up after a crash, and performs recovery for the transactions that it has not yet completed.

XA Superior Transaction recovery

Figure 4: XA Superior Transaction recovery

The protocols involved are specified as follows:

The interface between the XA Transaction Manager and the XA Superior Transaction Manager is specified in [XOPEN-DTP], with the addition of the implementation-specific XA Lookup event.

One of the differences between the OleTx model and the XA model, as far as the recovery process is concerned, is that in the OleTx model the recovery process is initiated by a resource manager that re-enlists, whereas in case of the XA model, the recovery process is initiated by an XA Transaction Manager.

The XA Transaction Manager requests a list of all those transactions in need of recovery, and makes calls on the XA Superior Transaction Manager to communicate their results using the XA Interface specified in [XOPEN-DTP].