You must also consider the level of security required for your environment and whether TIBCO Object Service Broker, IMS, and DB2 data must be updated in a single transaction. Refer to
Implementing Security and
Implementing Fail Safe Processing for more information.
Each class of the Gateway requires a PSB that defines all the IMS databases that you want to access from TIBCO Object Service Broker through that class of Gateway, and the processing options available for each database. You must define a database Program Control Block (PCB) for each database you need the Gateway to access. The PSB defined for the BMP, CICS DL/I and DRA interface is locked for the time of the TIBCO Object Service Broker transaction. The CICS interface can use different PSBs but only one per TIBCO Object Service Broker transaction.
If a database contains non-unique segments (no key or multiple sequence keys), define at least two identical PCBs. The first PCB is reserved for unique segment access. Subsequent PCBs are used to maintain the position in the database when accessing non-unique segment occurrences. The number of PCBs required is the maximum number of non-unique IMS tables that map to the same database, accessed in a single TIBCO Object Service Broker transaction.
If you always access an IMS database through a secondary index, include the PROCSEQ parameter with all PCBs defined for that database. If you access an IMS database using both primary and secondary processing sequences, complete the following steps:
If an instance of the Gateway uses Cross Memory Services to communicate with the Data Object Broker, ensure that all data sets in the STEPLIB concatenation list are APF authorized.
The Gateway uses the DL/I ROLB call to roll back any updates if they are required or requested. In order for the ROLB call to be successful, if using the DL/I interface, you must set the dynamic backout parameter to Yes (BKO=Y). An IEFRDER data set is also required for IMS logging. Ensure that this data set remains on DASD and is large enough to accommodate rollback processing. Refer to
Starting the Gateway for more information.