Avaya DECnet User Manual

Configuring DECnet
Services

Router Software Version 11.0
Site Manager Software Version 5.0

Part No. 114050 Rev. A
August 1996

4401 Great America Parkway 8 Federal Street
Santa Clara, CA 95054 Billerica, MA 01821

Copyright © 1988–1996 Bay Networks, Inc.

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ii 114050 Rev. A

Bay Networks Software License

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114050 Rev. A iii

Bay Networks Software License

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(continued)

iv 114050 Rev. A

Contents

Configuring DECnet Services
About This Guide

Before You Begin .............................................................................................................xiii

Conventions .................................................................................................................... xiv

Acronyms ......................................................................................................................... xv

Ordering Bay Networks Publications ...............................................................................xv

Technical Support and Online Services

Bay Networks Customer Service ...................................................................................xviii

Bay Networks Information Services ................................................................................ xix

World Wide Web ...................................................................................................... xix

Customer Service FTP ............................................................................................. xix

Support Source CD ...................................................................................................xx

CompuServe ............................................................................................................. xx

InfoFACTS ................................................................................................................ xxi

How to Get Help ....................................................................................................... xxi

Chapter 1
DECnet Overview

DECnet Network Organization .......................................................................................1-1

DECnet Phase IV Organization ................................................................................1-1

DECnet Phase V Organization .................................................................................1-3

Routing DECnet Packets across the Network ................................................................1-4

The Routing Process ................................................................................................1-5

Update Process .................................................................................................1-5

Listening Process ..............................................................................................1-6

Decision Process ...............................................................................................1-6

Forwarding Process ...........................................................................................1-8

The Designated Router ............................................................................................1-9

114050 Rev. A v

DECnet IV to V Transition .............................................................................................1-10

Translating DECnet Addresses ..............................................................................1-10

Translating Data Packets ........................................................................................1-11

Phase IV to Phase V ..............................................................................................1-12

Phase V to Phase IV ..............................................................................................1-12

Advertising Routes .................................................................................................1-13

DECnet IV to V Basic Transition Strategy ..............................................................1-13

Static Routes ................................................................................................................1-14

Static Adjacency Support .............................................................................................1-16

For More Information ....................................................................................................1-19

Chapter 2
Enabling DECnet Services

Enabling DECnet Phase IV on an Interface ....................................................................2-2

Chapter 3
Editing DECnet Parameters

Accessing DECnet Parameters ......................................................................................3-2

Editing DECnet Global Parameters ................................................................................3-3

DECnet Global Parameter Descriptions ...................................................................3-4

Editing DECnet Interface Parameters .............................................................................3-9

DECnet Interface Parameter Descriptions .............................................................3-11

Configuring Static Routes .............................................................................................3-18

Adding a Static Route ............................................................................................3-18

DECnet Static Route Parameter Descriptions .................................................3-19

Editing Static Route Parameters ............................................................................3-23

Deleting a Static Route ..........................................................................................3-23

Configuring Static Adjacencies .....................................................................................3-23

Adding a Static Adjacency .....................................................................................3-24

DECnet Static Adjacency Parameter Descriptions ..........................................3-27

Editing Static Adjacency Parameters .....................................................................3-29

Deleting a Static Adjacency ...................................................................................3-30

Configuring the DECnet IV to V Transition ...................................................................3-30

Creating the DECnet IV to V Transition ..................................................................3-31

DECnet IV to V Transition Parameter Descriptions .........................................3-31

Editing the DECnet IV to V Transition Parameters .................................................3-33

vi 114050 Rev. A

Deleting the DECnet IV to V Transition ..................................................................3-33

Deleting DECnet from the Router .................................................................................3-34

Appendix A
DECnet Parameter Default Settings

Index

114050 Rev. A vii

Figures

Figure 1-1. DECnet Phase IV Address .......................................................................1-2

Figure 1-2. Bay Networks Router with Multiple DECnet Addresses ...........................1-3

Figure 1-3. Calculating the Least-Cost Path ...............................................................1-6

Figure 1-4. Least-Cost Path to a Destination .............................................................1-8

Figure 1-5. DECnet Phase IV to Phase V Address Mapping ...................................1-11

Figure 1-6. Translation of a DECnet Phase IV Data Packet to a

Phase V CLNP Packet ...........................................................................1-12

Figure 1-7. Static Routes Defined for Routers Residing in Different Areas ..............1-15

Figure 1-8. Static Adjacencies Defined for Routers Residing in the Same Area ......1-17

Figure 1-9. Static Adjacencies Defined for Routers Residing

in Different Areas ...................................................................................1-18

Figure 2-1. DECnet IV Configuration Window ............................................................2-2

Figure 3-1. Configuration Manager Window ...............................................................3-2

Figure 3-2. Edit DECnet Global Parameters Window .................................................3-3

Figure 3-3. DECnet IV Interface List Window ...........................................................3-10

Figure 3-4. DECnet Static Routes List Window ........................................................3-18

Figure 3-5. DECnet Static Routes Configuration Window ........................................3-19

Figure 3-6. Circuit List Window ................................................................................3-24

Figure 3-7. Circuit Definition Window .......................................................................3-25

Figure 3-8. DECnet Static Adjacent Hosts List Window ...........................................3-26

Figure 3-9. DECnet Static Adjacency Configuration Window ...................................3-26

Figure 3-10. Create DECnet IV to V Transition Parameters Window .........................3-31

114050 Rev. A ix

Tables

Table 1-1. Router Forwarding Based on the Destination Address

in the Packet Header ................................................................................1-9

Table A-1. DECnet Phase IV Global Parameters ..................................................... A-1

Table A-2. DECnet Phase IV Interface Parameters ................................................. A-2

Table A-3. DECnet Static Route Parameters ........................................................... A-2

Table A-4. DECnet Static Adjacency Parameters .................................................... A-3

Table A-5. DECnet IV to V Transition Parameters .................................................... A-3

114050 Rev. A xi

If you are responsible for configuring Bay Networks™ router software for DECnet
services, you need to read this guide. It explains

• How DECnet services work (Chapter 1)

• How you configure a DECnet interface (Chapter 2)

• How to edit DECnet global and interface parameters and configure static
routes, static adjacencies, and the DECnet IV to V Transition (Chapter 3)

Before You Begin

Before using this guide, you must complete the following procedures. For a new
router:

About This Guide

• Install the router (refer to the installation manual that came with your router).

• Connect the router to the network and create a pilot configuration file (refer to

Quick-Starting Routers and BNX Platforms, Connecting BayStack AN and
ANH Systems to a Network, or Connecting ASN Routers and BNX Platforms
to a Network).

• Create and save a configuration file that has at least one DECnet interface
(refer to Configuring Routers for instructions).

• Retrieve the configuration file in local, remote, or dynamic mode (refer to
Configuring Routers for instructions).

Make sure that you are running the latest version of Bay Networks Site Manager
and router software. For instructions, refer to Upgrading Routers from Version
7–10.xx to Version 11.0.

114050 Rev. A xiii

Configuring DECnet Services

Conventions

bold text Indicates text that you need to enter, command names,

italic text Indicates variable values in command syntax

quotation marks (“ ”) Indicate the title of a chapter or section within a book.

screen text Indicates data that appears on the screen.

separator ( > ) Separates menu and option names in instructions and

and buttons in menu paths.
Example: Enter

wfsm &

Example: Use the dinfo command.
Example: ATM DXI > Interfaces > PVCs identifies the

PVCs button in the window that appears when you
select the Interfaces option from the ATM DXI menu.

descriptions, new terms, file and directory names, and
book titles.

Example:

Set Bay Networks Trap Monitor Filters

internal pin-to-pin wire connections.
Example: Protocols > AppleTalk identifies the
AppleTalk option in the Protocols menu.

Example: Pin 7 > 19 > 20

vertical line (|) Indicates that you enter only one of the parts of the

command. The vertical line separates choices. Do not
type the vertical line when entering the command.
Example: If the command syntax is

show at routes | nets, you enter either
show at routes or show at nets, but not both.

xiv 114050 Rev. A

Acronyms

AFI authority format identifier
CLNP Connectionless Network Protocol
DSP Domain Specific Part
ES-IS End System to Intermediate System
IDI Initial Domain Identifier
IDP Initial Domain Part
IS-IS Intermediate System to Intermediate System
MAC media access control
MIB Management Information Base
NSAP Network Service Access Point
OSI Open Systems Interconnection
SMDS Switched Multimegabit Data Services
WAN wide area network

Ordering Bay Networks Publications

About This Guide

To purchase additional copies of this document or other Bay Networks

™

publications, order by part number from the Bay Networks Press

at the following

telephone or fax numbers:

• Telephone - U.S./Canada 1-888-4BAYPRESS

• Telephone - International 1-510-490-4752

• Fax [phone]

You can also use these numbers to request a free catalog of Bay Networks Press
product publications.

114050 Rev. A xv

Technical Support and Online Services

To ensure comprehensive network support to our customers and partners
worldwide, Bay Networks Customer Service has Technical Response Centers
in key locations around the globe:

• Billerica, Massachusetts

• Santa Clara, California

• Sydney, Australia

• Tokyo, Japan

• Valbonne, France

The Technical Response Centers are connected via a redundant Frame Relay
Network to a Common Problem Resolution system, enabling them to transmit and
share information, and to provide live, around-the-clock support 365 days a year.

Bay Networks Information Services complement the Bay Networks Service
program portfolio by giving customers and partners access to the most current
technical and support information through a choice of access/retrieval means.
These include the World Wide Web, CompuServe, Support Source CD, Customer
Support FTP, and InfoFACTS document fax service.

114050 Rev. A xvii

Configuring DECnet Services

Bay Networks Customer Service

If you purchased your Bay Networks product from a distributor or authorized
reseller, contact that distributor’s or reseller’s technical support staff for assistance
with installation, configuration, troubleshooting, or integration issues.

Customers can also purchase direct support from Bay Networks through a variety
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To purchase any of the Bay Networks support programs, or if you have questions
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Region Telephone Number Fax Number

United States and
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1-800-2LANWAN; enter Express Routing
Code (ERC) 290 when prompted

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Asia/Pacific Region (612) 9927-8800 (612) 9927-8811
Latin America [phone] [phone]

In addition, you can receive information on support programs from your local
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from your authorized partner.

xviii 114050 Rev. A

Bay Networks Information Services

Bay Networks Information Services provide up-to-date support information as a
first-line resource for network administration, expansion, and maintenance. This
information is available from a variety of sources.

World Wide Web

The Bay Networks Customer Support Web Server offers a diverse library of
technical documents, software agents, and other important technical information
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A special benefit for contracted customers and resellers is the ability to access the
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• View a listing of support cases and determine the current status of any open
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Technical Support and Online Services

• Customize the listing of cases according to a variety of criteria, including
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• Communicate directly via e-mail with the specific technical resources
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The Bay Networks URL is http://www.baynetworks.com. Customer Service is a
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Customer Service FTP

Accessible via URL ftp://support.baynetworks.com (134.177.3.26), this site
combines and organizes support files and documentation from across the
Bay Networks product suite, including switching products from our Centillion™

®

and Xylogics
site lets you quickly locate information on any of your Bay Networks products.

114050 Rev. A xix

business units. Central management and sponsorship of this FTP

Configuring DECnet Services

Support Source CD

This CD-ROM -- sent quarterly to all contracted customers -- is a complete Bay
Networks Service troubleshooting knowledge database with an intelligent text
search engine.

The Support Source CD contains extracts from our problem-tracking database;
information from the Bay Networks Forum on CompuServe; comprehensive
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software patches and fixes; and complete information on all Bay Networks
Service programs.

You can run a single version on Macintosh Windows 3.1, Windows 95,
Windows NT, DOS, or UNIX computing platforms. A Web links feature enables
you to go directly from the CD to various Bay Networks Web pages.

CompuServe

For assistance with noncritical network support issues, Bay Networks Information
Services maintain an active forum on CompuServe, a global bulletin-board
system. This forum provides file services, technology conferences, and a message
section to get assistance from other users.

The message section is monitored by Bay Networks engineers, who provide
assistance wherever possible. Customers and resellers holding Bay Networks
service contracts also have access to special libraries for advanced levels of
support documentation and software. To take advantage of CompuServe’s
recently enhanced menu options, the Bay Networks Forum has been
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We recommend the use of CompuServe Information Manager software to access
these Bay Networks Information Services resources. To open an account and
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your CompuServe account, you can reach us with the command

xx 114050 Rev. A

GO BAYNET.

InfoFACTS

InfoFACTS is the Bay Networks free 24-hour fax-on-demand service. This
automated system has libraries of technical and product documents designed to
help you manage and troubleshoot your Bay Networks products. The system
responds to a fax from the caller or to a third party within minutes of being
accessed.

To use InfoFACTS in the United States or Canada, call toll-free 1-800-786-3228.
Outside North America, toll calls can be made to 1-408-764-1002. In Europe,
toll-free numbers are also available for contacting both InfoFACTS and
CompuServe. Please check our Web page for the listing in your country.

How to Get Help

Use the following numbers to reach your Bay Networks Technical Response
Center:

Technical Response Center Telephone Number Fax Number

Billerica, MA 1-800-2LANWAN [phone]
Santa Clara, CA 1-800-2LANWAN [phone]
Valbonne, France (33) 92-968-968 (33) 92-966-998
Sydney, Australia (612) 9927-8800 (612) 9927-8811
Tokyo, Japan (81) 3-5402-0180 (81) 3-5402-0173

Technical Support and Online Services

114050 Rev. A xxi

Chapter 1

DECnet Overview

This chapter shows how Bay Networks router software works with DECnet
services and describes the

• Organization of end nodes and routers in a DECnet network

• Transmission of messages from the Bay Networks router through the DECnet
network

• Routing decision process for a DECnet network

• DECnet IV to V Transition feature

• Purpose of static routes

• Static adjacency support

DECnet Network Organization

A DECnet network contains two types of nodes: end nodes and routers. End nodes
send and receive messages. Routers transmit messages to end nodes and other
routers on the network.

DECnet Phase IV Organization

DECnet Phase IV is a networking protocol that supports large networks (up to
approximately 64,000 nodes). You can divide each network into as many as 63
distinct areas; each area contains up to 1023 nodes. You must assign to each area
an Area ID, unique to the network. You must also assign to each node within an
area a Node ID, unique to the area.

114050 Rev. A 1-1

Configuring DECnet Services

Together, the Area ID and Node ID form a 16-bit DECnet Phase IV address
(Figure 1-1). The first 6 bits identify the area in which the node resides; the last 10
bits identify the node itself. Each DECnet Phase IV address must be unique within
the network.

6 bits

Area ID

Figure 1-1. DECnet Phase IV Address

10 bits

Node ID

DEC0001A

A Bay Networks router running the routing software for a DECnet Phase IV
network can service multiple areas; that is, you can assign a DECnet Phase IV
address to each of the router’s indi vidual interfaces, rather than to the entire router.
For example, if a router resides in multiple areas (has circuits connecting to more
than one area), you assign an Area ID and Node ID for each area to which it
connects. A router can also have several interfaces (each one with a unique Node
ID) in the same area.

Figure 1-2, circuits E21 and E22 have different DECnet addresses, e ven though

In
they connect to the same router. Note that each circuit’s address is still unique
within its area and within the DECnet network.

1-2 114050 Rev. A

DECnet Overview

Area 1

Circuit E21

Area ID = 1 Node ID = 3

DECnet Phase IV Address for
Circuit E21 = 1.3

Key

End Node

Area 10

101 102 10321

3

Circuit E22

100

Area ID = 10

DECnet Phase IV Address
for Circuit E21 = 10.100

Node ID = 100

Router

DEC0002A

Figure 1-2. Bay Networks Router with Multiple DECnet Addresses

DECnet Phase V Organization

DECnet Phase V is an implementation of the Open Systems Interconnection
(OSI) Connectionless-mode Network Layer protocols. These protocols include
Connectionless Network Protocol (CLNP), End System to Intermediate System
(ES-IS) protocol, and Intermediate System to Intermediate System (IS-IS)
protocol.

114050 Rev. A 1-3

Configuring DECnet Services

Each system in a DECnet Phase V network is assigned a Network Service Access
Point (NSAP) address. Each DECnet Phase V NSAP address must be globally
unique and can be from 10 to 20 bytes in length. However, a local DECnet
network does not need a unique address.

For more information about Phase V network organization and addressing, refer
to Chapter 1 of Configuring OSI Services.

Routing DECnet Packets across the Network

The Bay Networks routing software for DECnet services uses a datagram service
to route packets through the DECnet network. Routing within an area is called
Level 1 (or intra-area) routing; routing between areas is called Level 2 (or
interarea) routing.

You can configure the Bay Networks routing software to perform either Level 1
and Level 2 routing, or to perform Level 1 Only routing.

• Use Level 1 and Level 2 routing to maintain paths to all areas within a
DECnet network.

• Use Level 1 Only routing to maintain paths to only those systems within the
router’s local area. Level 1 Only routing prevents the sending of Level 2
routing updates, thus reducing traffic on an interface.

By default, the Bay Networks routing software for DECnet services performs both
types of routing. When the router performs both Level 1 and Le vel 2 routing, you
can configure each router interface as either Level 1 and Level 2, or as Level 1
Only.

When you configure the router to perform Level 1 Only routing, the router
maintains paths only to those systems within its local area. When the router
performs Level 1 Only routing, you must configure all router interfaces as Le v el 1
Only .

1-4 114050 Rev. A

When a Bay Networks router receives a packet, it examines the destination
address contained in the packet header. If the destination address is within the
same area as the router, the router forwards the packet toward the destination
system using the least-cost path. If the address is to another area, the router
behaves differently depending on whether the interface performs Level 1 and
Level 2 routing or Level 1 Only routing:

• If the router interface performs both Level 1 and Level 2 routing, the router
forwards the packet to the specified area using the least-cost path.

• If the router interface performs Level 1 Only routing, the router forwards the
packet to the nearest Level 2 router.

• If the router and all of its interfaces perform Level 1 Only routing, the router
forwards the packet to the nearest Level 2 router.

The Routing Process

Routing a DECnet packet through the network involves

• Updating adjacent routers on the availability of surrounding nodes and
circuits

DECnet Overview

• Listening for messages from adjacent routers identifying available nodes and
circuits

• Determining the routing path with the least cost

• Forwarding the packet to the specified adjacent node

Update Process

The Bay Networks router software for DECnet services continually monitors the
circuits directly attached to it. It periodically receives routing control messages
from its adjacent routers. These routing updates inform the router of the current
network topology. For example, if a circuit on a router fails, or another circuit is
added, the network topology changes. The router then generates and transmits
routing updates to all adjacent routers informing them of the changes. Timers
control how often the router sends out updates.

Routing updates describe which nodes in the local area are reachable (called node
or Level 1 topology updates), and which other areas in the network are reachable
(called area or Level 2 topology updates). Routers use this information to update
their routing tables.

114050 Rev. A 1-5