DIGITAL TCP/IP Services for OpenVMS

DIGITAL TCP/IP Services for OpenVMS

eSNMP Programming and Reference

Order Number: AA--R04BB--TE


January 1999

This manual provides information about building subagents using the Extensible Simple Network Management Protocol (eSNMP) application programming interface (API) provided with DIGITAL TCP/IP Services for OpenVMS.

Revision Information: This is a revised manual.

Operating Systems: OpenVMS Alpha Versions 7.1, 7.2 OpenVMS VAX Versions 7.1, 7.2

Software Version: DIGITAL TCP/IP Services
for OpenVMS Version 5.0





Compaq Computer Corporation Houston, Texas


January 1999

Compaq Computer Corporation makes no representations that the use of its products in the manner described in this publication will not infringe on existing or future patent rights, nor do the descriptions contained in this publication imply the granting of licenses to make, use, or sell equipment or software in accordance with the description.

Possession, use, or copying of the software described in this publication is authorized only pursuant to a valid written license from Compaq or an authorized sublicensor.

Compaq conducts its business in a manner that conserves the environment and protects the safety and health of its employees, customers, and the community.

© Compaq Computer Corporation 1999. All rights reserved.

The following are trademarks of Compaq Computer Corporation: ACMS, Alpha, Compaq, DDCMP, DEC, DECdtm, DECnet, DECNIS, DECserver, DECsystem, DIGITAL, DIGITAL UNIX, DNA, InfoServer, LAT, OpenVMS, PATHWORKS, POLYCENTER, ULTRIX, VAX, VMS, and the Compaq logo.

The following are third-party trademarks:

CRAY is a registered trademark of Cray Research, Inc.

HP and Hewlett-Packard are registered trademarks of Hewlett-Packard Company.

IBM and OS/2 are registered trademarks of International Business Machines Corporation.

Macintosh is a registered trademark of Apple Computer, Inc.

MS-DOS is a registered trademark of Microsoft Corporation.

MultiNet is a registered trademark of Process Software Corporation.

OSF/1 is a registered trademark of Open Software Foundation, Inc.

OSI is a registered trademark of CA Management, Inc.

PostScript is a registered trademark of Adobe Systems Incorporated.

SCO is a trademark of Santa Cruz Operations, Inc.

Sun, NFS, and PC-NFS are registered trademarks of Sun Microsystems, Inc.

UNIX is a registered trademark in the United States and other countries, licensed exclusively through X/Open Company Ltd.

All other trademarks and registered trademarks are the property of their respective holders.

ZK6530

This document is available on CD-ROM.

This document was prepared using VAX DOCUMENT, Version V3.2n.

Contents Index


Preface

The DIGITAL TCP/IP Services for OpenVMS product is Compaq's implementation of the TCP/IP networking protocol suite and internet services for OpenVMS Alpha and OpenVMS VAX systems.

A layered software product, DIGITAL TCP/IP Services for OpenVMS provides a comprehensive suite of functions and applications that support industry-standard protocols for heterogeneous network communications and resource sharing.

This manual describes the Extensible Simple Network Management Protocol (eSNMP) provided with DIGITAL TCP/IP Services for OpenVMS. This manual also describes the eSNMP application programming interface (API) and provides instructions for building additional subagents to manage vendor-specific equipment.

Intended Audience

This manual is for OpenVMS system or network programmers who want to manage network software and to build eSNMP subagents to manage their own equipment and applications. The system programmers who use this manual to create subagents are assumed to have an understanding of networking terminology and ASN.1 programming.

New and Changed Features

DIGITAL TCP/IP Services for OpenVMS Version 5.0 provides a new kernel based on the IPv4 kernel ported from DIGITAL UNIX Version 4.0D.1

Other new features include:

For information about changes to information in this document, see the DIGITAL TCP/IP Services for OpenVMS Release Notes.

Note

1 This kernel is based on the Berkeley Software Distribution (BSD) Versions 4.3 and 4.4 with enhancements from Compaq Computer Corporation.

Document Structure

This manual contains the following chapters:

Related Documentation

Table 1 lists the manuals available with this version of DIGITAL TCP/IP Services for OpenVMS.

Table 1 DIGITAL TCP/IP Services for OpenVMS Documentation
Manual Contents
DIGITAL TCP/IP Services for OpenVMS Release Notes This text file describes new features and changes to the software including installation, upgrade, configuration, and compatibility information. These notes also describe new and existing software problems and restrictions, and software and documentation corrections.

Print this text file at the beginning of the installation procedure and read it before you install DIGITAL TCP/IP Services for OpenVMS.

DIGITAL TCP/IP Services for OpenVMS Installation and Configuration This manual explains how to install and configure the DIGITAL TCP/IP Services for OpenVMS layered application product.
DIGITAL TCP/IP Services for OpenVMS User's Guide This manual describes how to use the applications available with DIGITAL TCP/IP Services for OpenVMS such as remote file operations, e-mail, TELNET, TN3270, and network printing. This manual also explains how to use these services to communicate with systems on private internets or on the worldwide Internet.
DIGITAL TCP/IP Services for OpenVMS Management This manual describes how to configure and manage the DIGITAL TCP/IP Services for OpenVMS product.

Use this manual with the DIGITAL TCP/IP Services for OpenVMS Management Command Reference manual.

DIGITAL TCP/IP Services for OpenVMS Management Command Reference This manual describes the DIGITAL TCP/IP Services for OpenVMS management commands.

Use this manual with the DIGITAL TCP/IP Services for OpenVMS Management manual.

DIGITAL TCP/IP Services for OpenVMS Sun RPC Programming This manual presents an overview of high-level programming using open network computing remote procedure calls (ONC RPC). This manual also describes the RPC programming interface and how to use the RPCGEN protocol compiler to create applications.
DIGITAL TCP/IP Services for OpenVMS System Service and C Socket Programming This manual describes how to use the OpenVMS system services and C Socket programming interfaces to develop network-based applications.
DIGITAL TCP/IP Services for OpenVMS eSNMP Programming and Reference This manual describes the Extensible Simple Network Management Protocol (eSNMP), the eSNMP application programming interface (API), and how to build additional subagents to manage vendor-specific equipment.

For additional information about the DIGITAL TCP/IP Services for OpenVMS products and services, access the DIGITAL OpenVMS World Wide Web site at the following URL:


http://www.openvms.digital.com 

You might find the Internetworking with TCP/IP: Principles, Protocols, and Architecture by Douglas Comer useful if you are looking for a comprehensive overview of the TCP/IP protocol suite.

Terminology

DIGITAL TCP/IP Services for OpenVMS Version 5.0 completes the change initiated several releases ago when the product name changed from "ULTRIX Connection (UCX)" to "DIGITAL TCP/IP Services for OpenVMS." To complete this change, the identifier "UCX" is replaced with "TCPIP" in the following cases:

DIGITAL TCP/IP Services for OpenVMS is used to mean both:

The auxiliary server is the DIGITAL TCP/IP Services for OpenVMS implementation of the UNIX internet daemon (inetd).

NFS is the DIGITAL TCP/IP Services for OpenVMS implementation of the NFS protocols, including the NFS server, the NFS client, and PC-NFS.

TN3270 means the TELNET client software that emulates IBM 3270 model terminals.

The term UNIX refers to the DIGITAL UNIX operating system. DIGITAL UNIX is fully compatible with Version 4.3 and Version 4.4 of the Berkeley Software Distribution (BSD).

Host and node both mean a system connected to an internet.

The term Internet refers to the global interconnection of networks, as defined by RFC 1208, which consists of large networks using TCP/IP to provide universal connectivity, reaching the Defense Advanced Projects Research Internet, MILNET, NSFnet, CERN, and many worldwide universities, government research labs, military installations, and business enterprises.

The term internet refers to private interconnected networks that use TCP/IP to connect together and function as one, virtual network.

Conventions

All IP addresses in this manual represent fictitious addresses. The following conventions apply to this manual.
Convention Meaning
UPPERCASE TEXT Indicates names of OpenVMS and DIGITAL TCP/IP Services for OpenVMS commands, options, utilities, files, directories, hosts, and users.
lowercase special type Indicates UNIX system output or user input, commands, options, files, directories, utilities, hosts, and users.
bold text Indicates a new term.
italic text Indicates a variable.
[Return] Indicates that you press the Return key.
[Ctrl/] x Indicates that you press the Control key while you press the key noted by x.
[ ] In command format descriptions, indicates the enclosed element is optional. You can enter as many as you want.
{ } In command format descriptions, indicates you must enter at least one listed element. For readability, each element is either listed on a separate line or separated by vertical bars (|). Unless otherwise instructed, use a space to separate these elements when using them with commands.
... Horizontal ellipsis points in examples indicate additional optional arguments have been omitted.
.
.
.
Vertical ellipsis points indicate omission of items from a code example or display example; the items are omitted because they are not important to the topic being discussed.

Reader's Comments

Compaq welcomes your comments on this manual.

Print or edit the online form SYS$HELP:OPENVMSDOC_COMMENTS.TXT and send us your comments by:
Internet openvmsdoc@zko.mts.dec.com
Fax 603 884-0120, Attention: OSSG Documentation, ZKO3-4/U08
Mail Compaq Computer Corporation
OSSG Documentation Group, ZKO3-4/U08
110 Spit Brook Rd.
Nashua, NH 03062-2698

How To Order Additional Documentation

Visit the OpenVMS Documentation World Wide Web site at the following URL to learn how to order additional documentation:


http://www.openvms.digital.com:81/ 

If you need help deciding which documentation best meets your needs, call 800-DIGITAL (800-344-4825).


Chapter 1
Overview

The Simple Network Management Protocol (SNMP) is the de facto industry standard for managing TCP/IP networks. The protocol defines the role of a network management station (NMS) and the SNMP agent. SNMP allows remote users on an NMS to monitor and manage network entities such as hosts, routers, X terminals, and terminal servers.

DIGITAL TCP/IP Services for OpenVMS (TCP/IP) provides support for SNMP with the Extensible Simple Network Management Protocol (eSNMP) software. Extensibility means that a single master agent can support any number of subagents. The DIGITAL implementation of eSNMP includes a master agent, two subagents, and an application programming interface (API) used to build additional subagents

This chapter provides an overview of the DIGITAL implementation of eSNMP. Topics include:

1.1 eSNMP Master Agent and Subagent Architecture

The eSNMP software manages network communication by having the master agent listen for requests and then passing the requests on to the appropriate subordinate agent called a subagent.

When a subagent starts, it tells the master agent the objects for which it is responsible. The master agent directs all requests for those objects to that subagent. Related objects are usually grouped together into a collection called a management information base (MIB). Generally, one subagent processes all the requests for a particular MIB.

Communication between the master agent and its subagents is by means of a protocol based on the Distributed Protocol Interface (DPI V2) described in RFC 1592.

Note

DPI V2 is an experimental protocol with which DIGITAL does not fully comply. DIGITAL used DPI as the basis for agent/subagent communication to make future implementations of standard protocols easier. DIGITAL plans to track and support standards that emerge in the area of eSNMP.

When a subagent starts, it establishes a connection to the master agent via a named socket. Communication between the master agent and subagent adhere to the following steps:

  1. The subagent periodically sends a read to the master agent and waits for a request for information.
  2. The master agent sends a request to the subagent (this completes the read).
  3. The subagent processes the request.
  4. The subagent sends the response to the master agent.
  5. The subagent returns to the waiting state and periodically sends a read to the master agent.

Figure 1-1 illustrates master agent and subagent communication.

Figure 1-1 Master Agent - Subagent Communication


1.1.1 The MIB-II Subagent

The MIB-II subagent gathers the information necessary to manage TCP/IP-based internets. This implementation of eSNMP includes the following MIB-II groups:

The Internet community, through RFC 1213, has described MIB-II for monitoring and managing TCP/IP applications. Chapter 3 describes the MIB-II standard as implemented in the DIGITAL TCP/IP Services for OpenVMS eSNMP software.

Note

The DIGITAL TCP/IP Services for OpenVMS eSNMP software does not support either the External Gateway Protocol (EGP) or the transmission group.

1.1.2 The Host Resources MIB Subagent

The Internet community, through RFC 1514, has described a Host Resources MIB for monitoring and managing Internet host systems. The eSNMP software implements a portion of this standard. Remote systems can monitor several operating system parameters including:

Chapter 3 describes the Host Resources MIB as implemented in this version of eSNMP.

1.2 The eSNMP API

The DIGITAL TCP/IP Services for OpenVMS implementation of eSNMP includes an API that provides programmers with many eSNMP routines they would otherwise have to develop.

The eSNMP API includes routines that provide the following functions:

Chapter 4 and Chapter 5 review how to create subagents for vendor-specific applications that you want to manage with eSNMP.

1.3 The MIB Compiler

The MIB Compiler processes the statements in the ASN.1 file and generates modules that are used by the developer to create subagent routines. For every ASN.1 input file that is processed using the MIB compiler, two output files, a <subtree>_TBL.H file and a <subtree>_TBL.C file, are generated.

The <subtree>_TBL.H file is a header file that contains the following:

The <subtree>_TBL.C file is an object file that contains the following:


Next Contents Index