OSI/MHS Gateway Programmatic Interface (GPI) Programming Guide

Planning Your Program
OSI/MHS Gateway Programmatic Interface (GPI) Programming Guide—424822-001
4-3
Planning for Gateway Fault Recovery
Planning for Gateway Fault Recovery
You can configure and manage the client program in any manner supported by Compaq.
You can structure the program for use as a NonStop process pair or any other process
type supported within the Compaq programming environment.
The mechanisms for fault recovery are somewhat different, depending on whether you
are doing outbound or inbound processing.
Outbound Fault Recovery
During outbound processing, the client program is responsible for objects in GPI library
memory space. If a failure occurs during outbound object management, objects in the
memory space must be restored by the client program.
Following successful completion of GPI_MT_TRANSFER_OUT_ , an object is
transferred to the GPI service output queue. The GPI service is responsible for objects
on the output queue. If a failure occurs, objects on the output queue are recovered
automatically by the GPI service.
Responsibility for outbound information is summarized in Table 4-1.
Figure 4-1. GPI Sessions and Gateways
Note. The GPI does not provide NonStop support to a client program that is bound to the GPI
library. If the client process is the active process of a NonStop process pair, and a takeover
occurs by the backup process, the backup process must reinitialize the GPI and begin new
sessions.
401CDT .CDD
Compaq System
Up to 15 sessions
Client
GPI
Library
Session 2
GIP
Session 1
GIP
Session 3
GIP
GATEWAY Object X
GATEWAY Object Y
GATEWAY Object
Z
GPI X.400 Gateway