Chapter 7 Definitions of API Agents in HATS HA [7.2]

7.2 API Agents to Detect Application Software Malfunctions

This section shows you how to program your own API agents so that they can detect the malfunctions in any application software being used on the active machine on the network. When an API agent detects a malfunction in an active application software, it will notify HATS HA so that HATS HA can transfer the active application from the current machine to another machine.

1. The following table provides an overview of the function calls to write API agents.

HA_api_open(char *jobname,char *interval).......registor API agent
...................HA_api_open("sybase","12")

HA_api_ok(char*jobname).................................when time interval send ok

HA_api_error(char *jobname)...........................................force job failover

HA_api_close(char *jobname)..................................close registor

Notes:

"HA_api_open" tells HATS HA that the API Agent has started to monitor a
specified application software. In this example, the specified application software
being monitored is "sybase," and the API Agent reports the application software's
status to HATS HA every 12 seconds.
"jobname" allows the API Agent to identify the current job, e.g., "sybase." It is
the same job as defined by "JOB=" in the configuration file.
"HA_api_ok" tells HATS HA that everything is OK with the application software.
"HA_api_error" tells HATS HA that something is wrong with the application
software. When HATS HA receives this message, it will transfer the current job
from the current machine to another machine.
"HA_api_close" tells HATS HA that the API Agent has stopped monitoring a
specified application software.
You may find the examples and library in the /usr/HA/ha_api directory.

	Table of Contents	Sec. 7-1	sec. 7-2