Using XA-Compliant Resources (XARs)

XA-compliant Resources (XARs)

For Enterprise Server to work properly with an RM, an XAR must be defined. An XAR definition must include:

• An xa_open string that includes standard RM fields and values, and optionally, additional Micro Focus-specific fields and values.
• An RM switch module
• An XAR ID that uniquely identifies the XAR. If compiling with the XAID compiler directive option, the XAR ID is used as the XAID value.

RM switch modules

A Micro Focus RM switch module is COBOL code that obtains the address of the XA switch data structure (xa_switch_t) provided by the RM, typically a database vendor. In addition, Micro Focus RM switch modules contain additional code that facilitates ease of use in Enterprise Server environments. RM switch modules are differentiated by their type, which is determined by the database vendor or other RM type. For example, you use an Oracle RM switch module type with Oracle databases, and so on.

With the exception of WebSphere MQ, Enterprise Developer provides the COBOL source code you need to compile, generating the appropriate switch modules. Once generated, you deploy an RM switch module to Enterprise Server, and then specify it as a part of your XAR definition.

XAR IDs

The XAR ID uniquely identifies your XAR, and is used in the following ways:

• To specify the XAR to use in batch jobs, namely:
  • The SYSTEM parameter for IDAEFT01
  • The CONNECT function's subsystem parameter for DSNALI
  • The IDENTIFY function's subsystem parameter for DSNRLI
• As the value for the XAID compiler directive option when compiling source code, if required.

For further details, see JCL Support and the XAID compiler directive option for COBSQL, OpenESQL or DB2 ECM.

XARs in Enterprise Server

In Enterprise Server, you can define XARs, and edit and delete XAR definitions. You can also control which XARs are loaded when a specific enterprise server region starts.