Envoy Application Programming Manual

Application Programming With Envoy
Envoy Application Programming Manual—427159-001
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Distributed Systems Management (DSM)
Distributed Systems Management (DSM)
The DSM product supports integrated management of system and network resources and
operations. DSM architecture consists of the following:
•
An operations environment providing applications and tools for operations tasks and
for controlling the subsystems
•
A subsystem environment in which subsystems (such as Envoy) and the objects they
control are managed (by the tools and applications in the operations environment)
•
A set of management services that support the programmatic interface between the
subsystem and operations environments
Subsystem Control Facility (SCF)
SCF is a DSM tool in the operations environment. It is a unified command interface that
simplifies the tasks of configuring, controlling, and collecting information about
Compaq subsystems. When you use SCF, you can choose either to let a person perform
an action (through a terminal) or to automate that action through a command (OBEY)
file. SCF returns display and error-message output to a terminal or to a log file.
The WAN Subsystem
Starting with G06.06, instructions for configuring Envoy are provided in a WAN wizard,
an online configuration tool, that interactively steps you through the SWAN
configuration process and provides quick and efficient alternatives to using multiple SCF
commands. The wizard also has an online help system that describes all the Envoy
profile modifiers. The WAN Wizard can be accessed through the Total Information
Manager (TIM) or through the TSM client application.
TSM
TSM brings up and maintains NonStop™ Himalaya S-series servers. Components of
TSM enable you to plan network, server, workstation, and user configurations for your
system.
Guardian 90 File-System Procedure Calls
Once the various lines have been characterized, you interact with them by issuing
Guardian 90 file-system procedure calls. You first open (activate) each line by calling
the OPEN procedure. Once the line is opened, you use WRITE calls to transmit data and
READ calls to accept incoming data. You can also use other file-system procedures such
as WRITEREAD, CONTROL, SETMODE, DEFINELIST, CHANGELIST, AWAITIO,
and so on. When you have finished using a line, you close (deactivate) that line by
calling the CLOSE procedure.
When Guardian 90 passes I/O requests to application programs, an Envoy I/O process
acquires the necessary system buffer space, monitors the state of all open lines for which
it is responsible, and returns completion status (and data for read operations) to the
application process.