Availability Guide for Application Design

Availability Through Process-Pairs and Monitors
Availability Guide for Application Design—525637-004
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HP Process Monitors
HP Process Monitors
HP provides the following process monitors:
•
The Tuxedo transaction-processing environment described in Section 5, Increasing
the Availability of Tuxedo Applications
•
The PATHWAY transaction-processing environment described in Section 6,
Availability in the Pathway Transaction-Processing Environment
•
The Kernel subsystem (G-series systems only) described at the end of this section
These process monitors provide a mechanism for creating process persistence without
having to code your own process-monitor process pair. The process persistence
provided can be immediate or initialized (as described in Section 1, What Is Application
Availability?). The level of persistence depends upon the application and the process
monitor used.
The advantage of using these process monitors is the cost and time saved by using
existing software instead of writing your own. The disadvantage is that you lose some
of the ability to perform application-specific diagnostic and recovery steps before
restarting a process.
The Kernel Subsystem
The Kernel subsystem can be configured to automatically start or restart an application
process. A Subsystem Control Facility (SCF) command interface allows active or
automated management of configured processes.
The Kernel subsystem provides:
•
The persistent-process functionality of the Pathway environment for applications
that do not use the Pathway or Tuxedo environments.
•
The persistent-process functionality of a site-written monitor-process pair.
•
A means to start and manage process-pair applications.
•
A minimal level of operational control for applications that have no command
interpreter interface.
Refer to the SCF Reference Manual for the Kernel Subsystem for more information.