Introduction to Networking for NonStop S-Series Servers

Managing Communications Subsystems
Introduction to Networking for HP NonStop S-Series Servers—520670-005
4-5
Management Interfaces
Programmatic Command Interface
Many communications subsystems have programmatic command interfaces based on
a set of procedure calls, definitions, and conventions known collectively as the
Subsystem Programmatic Interface (SPI). The programmatic commands available
through SPI parallel those available in the interactive interface, so you can write
applications that automate operator functions you would otherwise perform
interactively, such as issuing subsystem commands or retrieving event messages.
Your application uses SPI to build and decode management messages. It exchanges
those messages with a process called the Subsystem Control Point (SCP), which
interacts with the communications subsystems. Specifically, SCP is a data
communications management process. It provides the management interface to all
communications subsystems, so a management application can control multiple
subsystems without the overhead of establishing multiple process-to-process
relationships.
Figure 4-2 illustrates the relationships among SPI, SCP, and management
applications.
SCP can communicate directly with an IOP such as X25AM, or it can communicate
with a manager process, which in turn interfaces with one or more IOPs. A manager
process is likely to exist where multiple subsystems share management services. For
example, the Port Access Method (PAM) manager process, PAMMAN, performs
management services for the PAM subsystem in the DSM environment. Complex
subsystems like SNAX/XF are also likely to include manager processes.
Figure 4-2. SPI Messages Flow Between a Management Application and SCP
Management
Application
Subsystem Control
Point (SCP)
SPI Messages
Communications Subsystems
VST015.vsd