TS/MP Release Supplement

ACS Subsystem
HP NonStop TS/MP Release Supplement—546055-006
1-7
Improved Application Availability
For more information on the SCF interface and SCF commands for the ACS
subsystem, see Section 8, SCF Command Reference for the ACS Subsystem
.
Before starting the TS/MP Pathsend requesters, you must first use SCF commands to
start the ACS subsystem. For more information, see Starting the ACS Subsystem
($ZACS).
Improved Application Availability
ACS subsytem provides improved availability and scalability to the Pathway/iTS 1.1
application and other TS/MP applications. It allows you to run multiple Pathway
environments on a single NonStop system, with replicated server classes, known as
single logical Pathway domain. During the ACS subsystem configuration, pass the
ACSCTL file (containing configuration information pertaining to the Pathway
applications that are grouped under a single logical domain name) location into the
subsystem.
For information on the ACS subsystem configuration and startup, see Section 6,
Installing and Configuring. For more information on the ACSCTL file syntax, see
ACSCTL File Configuration
.
When Pathsend requests are sent to the Pathway domain name (and not to a specific
PATHMON process), ACS core processes find the suitable PATHMON process and the
server class to serve the Pathsend request. When one of the participating PATHMON
processes is brought down for a configuration change, the send requests are
automatically redirected to the other PATHMON processes to maintain application
availability. On a similar note, when one server class under one PATHMON
environment is either frozen or brought down for a configuration change, the send
requests are automatically redirected to the same server class under other PATHMON
processes in the same Pathway domain.
Figure 1-3
depicts the Pathway domain concept in the ACS subsystem.
Note. During the ACS subsystem configuration, if you do not pass the ACSCTL file location
into the subsystem, all requests will be sent only to the PATHMONs and not to the Pathway
domain.