Compaq AA-Q88CE-TE manual XA Support, New Qualifier to Create Facility Command

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XA Support

This appendix explains how RTR may be used with a X/OPEN Distributed Transaction Processing (DTP) conformant Resource Manager.

C.1 Introduction

The X/OPEN Distributed Transaction Processing (DTP) architecture defines a standard interface that lets application programs share resources provided by resource managers. The XA interface uses the two-phase commit protocol to commit transactions, and is a system-level bidirectional interface between the transaction manager (TM) and the resource manager (RM). In the RTR environment, RTR is the transaction manager and database software such as ORACLE8 is the resource manager.

Without XA, an RTR application must deal with replayed transactions after server recovery delivered with rtr_mt_msg1_uncertain; the application has to check if the traansaction has been committed to the database. With XA, the application does not need to be concerned with this problem.

The XA library is an external interface that enables a transaction manager to coordinate global transactions. These can include opening a resource manager, starting a transaction, rolling back a transaction, preparing and committing a transaction, and closing a resource manager. With XA, RTR can connect directly to a resource manager such as ORACLE8.

C.1.1 MONITOR XA

Monitors the internal status of XA interface activities. The command displays counters containing information such as the number of XA calls, call status (success or failure), and the number of read-only transactions. Provides counts for the open, close, start, end, prepare, commit, rollback, and recovery commands.

Command Syntax: MONITOR XA

C.1.2 New Qualifier to CREATE FACILITY Command

The CREATE FACILITY command has a new qualifier that references the defined resource manager. All resource managers that will be accessed by a facility must be specified. All transactions to these resource managers are recovered when the facility is created.

Command Syntax:

CREATE FACILITY facility_name /frontend=... /backend=... /router=...

/resource_manager=(RM_1, RM_2)

where:

XA Support C–1