Legal Notices

The information in this document is subject to change without notice.

Hewlett-Packard makes no warranty of any kind with regard to this manual, including, but not limited to, the implied warranties of merchantability and ???tness for a particular purpose. Hewlett-Packard shall not be held liable for errors contained herein or direct, indirect, special, incidental or consequential damages in connection with the furnishing, performance, or use of this material.

Warranty

A copy of the speci???c warranty terms applicable to your Hewlett-Packard product and replacement parts can be obtained from your local Sales and Service Of???ce.

U.S. Government License

Proprietary computer software. Valid license from HP required for possession, use or copying. Consistent with FAR 12.211 and 12.212, Commercial Computer Software, Computer Software Documentation, and Technical Data for Commercial Items are licensed to the U.S. Government under vendor's standard commercial license.

Copyright Notice

Copyright ?? 1997-2003 Hewlett-Packard Development Company L.P. All rights reserved. Reproduction, adaptation, or translation of this document without prior written permission is prohibited, except as allowed under the copyright laws.

?? Copyright 1979, 1980, 1983, 1985-93 Regents of the University of California

This software is based in part on the Fourth Berkeley Software Distribution under license from the Regents of the University of California.

??Copyright 1980, 1984, 1986 Novell, Inc.

??Copyright 1986-1992 Sun Microsystems, Inc.

??Copyright 1985-86, 1988 Massachusetts Institute of Technology.

2

??Copyright 1989-93 The Open Software Foundation, Inc.

??Copyright 1986 Digital Equipment Corporation.

??Copyright 1990 Motorola, Inc.

??Copyright 1990, 1991, 1992 Cornell University

??Copyright 1989-1991 The University of Maryland

??Copyright 1988 Carnegie Mellon University

Trademark Notices

UNIX?? is a registered trademark in the United States and other countries, licensed exclusively through The Open Group.

Intel?? Itanium?? Processor Family is a trademark of Intel Corporation in the U.S. and other countries and is used under license.

3

Contents

About This Document

1. Overview

The mrouted Routing Daemon . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 Multicasting Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 DVMRP Protocol . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 IP Multicast Addresses . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 Multicast Groups. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

The gated Routing Daemon . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 Advantages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 Deciding When to Use gated . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 Routing Protocols . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24

2. Con???guring mrouted

How to Con???gure mrouted . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31 Con???guration Commands. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31 Starting mrouted . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36 Verifying mrouted Operation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37 Displaying mrouted Routing Tables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38 Multicast Routing Support Tools . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41 The mrinfo Tool . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41 The map-mbone Tool. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41 The netstat Tool . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41

3. Con???guring gated

Con???guration Overview. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45 Con???guring gated . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46 Converting the Con???guration File from 3.0 to 3.5.9 . . . . . . . . . . . . . . . . . . . . . . . . . . 49 Con???guring the RIP Protocol . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50 RIP Protocol Statement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50 Con???guration Options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53 Simple RIP Con???guration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54 A: End System on a LAN with RIP Routers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54 B: RIP Router . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55 Example of a Large RIP Con???guration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55 A: Cluster Node (or Isolated Node). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56 B: Cluster (or Root) Server Node . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57 C: End System on a LAN with RIP Routers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57

5

Contents

D: Major Router. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58

E: Major Router . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58 Controlling RIP Traf???c . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58 Con???guring the OSPF Protocol . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60 Planning Your OSPF Con???guration. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63 Enabling OSPF . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64 De???ning Areas . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65 The networks Statement. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66 The interface Statement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67 Stub Areas . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74 De???ning Backbones . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76 Authentication . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77 Cost . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79 AS External Routes (AS Boundary Routers Only) . . . . . . . . . . . . . . . . . . . . . . . . . . . 80 Sample OSPF Con???guration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83 A: Internal Router (Non-Stub Area). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83 B: Area Border Router . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84 C: Internal Router (Stub Area). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 85 Accessing the OSPF MIB . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86

Con???guring RDP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 87 RDP Server . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 87 RDP Client . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 88 Customizing Routes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90 Specifying a Default Router . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90 Installing Static Routes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90 Setting Interface States . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91 Specifying Tracing Options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 92 Specifying Route Preference . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 94 Importing and Exporting Routes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 97 The import Statement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 97 The export Statement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 97 Examples of import and export Statements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98 Starting gated. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 99 Verifying That gated Is Running . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 100 Troubleshooting gated . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 101 Checking for Syntax Errors in the Con???guration File . . . . . . . . . . . . . . . . . . . . . . . 101

6

Contents

Tracing gated Activity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 101 Operational User Interface for gated ??? gdc . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 102 The gated Routing Table . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 103 The ripquery Tool . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 103 The ospf_monitor Tool . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 103 Common Problems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 104

Problem 1: gated does not act as expected. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 104

Problem 2: gated deletes routes from the routing table.. . . . . . . . . . . . . . . . . . . . 106

Problem 3: gated adds routes that appear to be incorrect. . . . . . . . . . . . . . . . . . . 107

Problem 4: gated does not add routes that you think it must. . . . . . . . . . . . . . . . 108

Index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 109

7

Contents

8

About This Document

This manual describes the various routing daemons supported in the HP-UX 11i v2 operating system.It is one of the ???ve new manuals documenting the Internet Services suite of products. See ???Related Documentation??? on page 11 for a list of the other new Internet Services manuals. These manuals replace the manual Installing and Administering Internet Services (B2355-90685), which was shipped with previous releases of the operating system.

This manual assumes that the HP-UX 11i v2 operating system software and the appropriate ???les, scripts, and subsets are installed.

Intended Audience

This manual is intended for system and network administrators responsible for managing the Routing Services. Administrators are expected to have knowledge of operating system concepts, commands, and the various routing protocols. It is also helpful to have knowledge of Transmission Control Protocol/Internet Protocol (TCP/IP) networking concepts and network con???guration; this manual is not a TCP/IP or a routing tutorial.

HP-UX Release Name and Release Identi???er

Each HP-UX 11i release has an associated release name and release identi???er. The uname (1) command with the -r option returns the release identi???er. Table 1 shows the releases available for HP-UX 11i.

9

Publishing History

Table 2 provides, for a particular document, the manufacturing part number, the respective operating systems, and the publication date.

What Is in This Document

HP-UX Routing Services Administrator???s Guide is divided into chapters, each of which contain information about con???guring the routing services.

10

Related Documentation

For more information about the Internet Services suite of products, see the following books:

???HP-UX Internet Services Administrator???s Guide

Provides an overview of the Internet Services products and describes how to install and con???gure them on your HP-UX 11i v2 operating system. You can access this manual at the following URL:

http://www.docs.hp.com/hpux/netcom/index.html#Internet%2

0Services

???HP-UX Mailing Services Administrator???s Guide

Provides information about the Mail User Agents (elm, mailx, mail) and Mail Transport Agent (Sendmail) used in the HP-UX 11i v2 operating system. This manual also contains a description of con???guring and administering Sendmail on your system. You can access this manual at the following URL:

http://www.docs.hp.com/hpux/netcom/index.html#Internet%20Servic es

???HP-UX IP Address and Client Management Administrator???s Guide

Provides an overview of the IP address and client management implementations on the HP-UX 11i v2 operating system, where BIND, DHCPv6, and SLP deal with client management, and NTP deals with IP address management. You can access this manual at the following URL:

http://www.docs.hp.com/hpux/netcom/index.html#Internet%2

0Services

???HP-UX Remote Access Services Administrator???s Guide

Provides information about the Remote Access Services available in the HP-UX 11i v2 operating system: r-commands, WU-FTP, and telnet. You can access this manual at the following URL:

http://www.docs.hp.com/hpux/netcom/index.html#Internet%2

0Services

???Request for Comments (RFC)

11

Many sections of this manual refer to RFCs for more information about certain networking topics. These documents publicize Internet standards, new research concepts, and status memos about the Internet. You can access the full range of RFC documents and more information about the Internet Engineering Task Force (IETF) at the following URL:

http://www.ietf.org/rfc.html

You can obtain additional information about mrouted and IP multicast routing from the following RFC (Request for Comment) documents:

???RFC 1075: Distance-Vector Multicast Routing Protocol

???RFC 1112: Host Extensions for IP Multicasting

???Other Documents

HP does not maintain and own the following information. As such, their content and availability are subject to change without notice.

The MBONE FAQ

The Multicast Backbone (MBONE) is a virtual network implemented on top of the physical Internet. It supports routing of IP multicast packets. It originated as a cooperative, volunteer effort to support experimentation in audio and video teleconferencing over the Internet. You can ???nd an HTML-formatted version of the MBONE FAQ at the URL:

http://www.ripe.net/rite/wg/mbone/eu-faq.html

???iknow Topics of Interest

HP iknow Topics of Interest describe some networking concepts and tasks, as well as other topics. You can ???nd these documents on the HP-UX networking communications home page at the following URL

http://docs.hp.com/iknow

Typographical Conventions

This document uses the following typographic conventions:

12

HP Encourages Your Feedback

HP welcomes any comments and suggestions you have on this manual.

You can send your comments in the following ways:

???Internet electronic mail: netinfo_feedback@cup.hp.com

???Using a feedback form located at the following URL: http://docs.hp.com/assistance/feedback.html

Please include the following information along with your comments:

???The full title of the manual and the part number. (The part number appears on the title page of printed and PDF versions of a manual.)

???The section numbers and page numbers of the information on which you are commenting.

13

???The version of HP-UX that you are using.

14

1 Overview

A router is a device that has multiple network interfaces and that transfers Internet Protocol (IP) packets from one network or subnet to another within an internetwork. In many IP-related documents, this device is also referred to as a gateway. The term router is used in this

Overview

manual. The router stores all the routing information in the form of a routing table. Routing tables contain the routes to reach a particular network, and also identify the router to which the datagram packet can be passed for this purpose. The routing tables must contain the latest routing information. Routing protocols perform the task of updating the routing tables with the latest routing information.

The primary function of a routing protocol is to exchange routing information with other routers. Routing daemons perform the task of exchanging routing information with other routers. The routing daemons supported on the HP-UX 11i v2 operating system are mrouted and gated 3.5.9.

A detailed description of the routing daemons, their con???guration and troubleshooting information is provided in this manual.

This chapter contains information about the following topics:

??????The mrouted Routing Daemon??? on page 17

??????The gated Routing Daemon??? on page 22

Overview

The mrouted Routing Daemon

of the multicast datagrams. You can achieve this by using topological knowledge of the network to implement a multicast forwarding algorithm called Truncated Reverse Path Broadcasting (TRPB).

mrouted structures routing information in the form of a pruned broadcast delivery tree that contains routing information. mrouted structures routing information only to those subnets that have members of the destination multicast group. In other words, each router determines which of its virtual network interfaces are in the shortest path tree. In this way, DVMRP can determine if an IP multicast datagram needs to be forwarded. Without such a feature, the network bandwidth can easily be saturated with the forwarding of unnecessary datagrams.

Because DVMRP routes only multicast datagrams, you must handle routing of unicast or broadcast datagrams using a separate routing process.

To support multicasting across subnets that do not support IP multicasting, DVMRP provides a mechanism called tunnelling. Tunnelling forms a virtual point-to-point link between pairs of mrouted routers by encapsulating the multicast IP datagram within a standard IP unicast datagram using the IP-in-IP protocol (IP protocol number 4). This unicast datagram, containing the multicast datagram, is then routed through the intervening routers and subnets. When the unicast datagram reaches the tunnel destination, which is another mrouted router, the unicast datagram is stripped away and the mrouted daemon forwards the multicast datagram to its destinations.

Figure 1-1 shows a tunnel formed between a pair of mrouted routers.

Figure 1-1 Tunnel Made with mrouted Routers

Tunnel

Overview

The mrouted Routing Daemon

In this ???gure, the mrouted router R1 receives a multicast packet from node M. Because R1 is con???gured as one end of a tunnel, R1 encapsulates the IP multicast packet in a standard unicast IP packet addressed to the mrouted router R2. The packet, now treated as a normal IP packet, is sent through the intervening nonmulticast network to R2. R2 receives the packet and removes the outer IP header, thereby restoring the original multicast packet. R2 then forwards the multicast packet through its network interface to node N.

The ???rst 4 bits (0 through 3) identify the address as a multicast address. Bits 4 through 31 identify the multicast group. Multicast addresses are in the range 224.0.0.0 through 239.255.255.255. Addresses 224.0.0.0 through 224.0.0.255 are reserved, and address 224.0.0.1 is permanently assigned to the all hosts group. The all hosts group is used to reach all the hosts on a local network that participate in IP multicasting. The addresses of other permanent multicast groups are published in RFC 1060 (Assigned Numbers, March 1990).

You can use IP multicast addresses only as destination addresses, and they must never appear in the source address ???eld of a datagram. Internet Control Message Protocol (ICMP) error messages are not generated for multicast datagrams.

Because IP Internet addressing is a software manifestation of the underlying physical network, you must map IP addresses to physical addresses that the hardware comprising the network understands.

Overview

The mrouted Routing Daemon

Normally, IP multicast addresses are mapped to 802.3 or Ethernet multicast addresses. The IP multicasting addressing scheme, similar to Ethernet???s scheme, uses the datagram???s destination address to indicate multicast delivery.

When an IP multicast address is mapped to an Ethernet multicast address, the low-order 23 bits of the IP multicast address are placed into the low-order 23 bits of the special Ethernet multicast address. The hexadecimal value of the special Ethernet multicast address is 01-00-5E-00-00-00. The resultant Ethernet address, however, is not unique, because only 23 out of the 28 bits representing the multicast address are used.

Multicast Groups

A multicast group comprises hosts with an intention to join the multicast group by listening to the same IP multicast address. Group membership is dynamic, that is, a host may join or leave a group at any time. A host may be a member of one or more groups simultaneously. Additionally, a host is allowed to send multicast datagrams to a group without being a member of the group.

You can assign multicast addresses to transient groups because the multicast address are often temporary. A typical transient group scenario is when users run an application that dynamically registers to speci???c multicast addresses, which are discarded later when all members of the group have left. Some multicast addresses may be assigned to permanent groups that always exist, even when their membership is empty.

Both hosts and mrouted routers that participate in IP multicasting use the Internet Group Management Protocol (IGMP) to communicate multicast group information among themselves. Hosts use IGMP to inform mrouted routers that they are joining a group. mrouted routers use IGMP to pass multicast routing information to other mrouted routers, and to check whether a host is still an active group member.

The underlying TCP/IP stack must support ICMP to participate in IP multicasting. While IGMP de???nes a standard for communicating information, it does not de???ne a standard for how the multicast information is propagated among multicast routers. Consequently, DVMRP enables multicast routers to ef???ciently communicate group membership information among themselves. DVMRP uses IGMP messages to carry routing and group membership information. DVMRP

Overview

The mrouted Routing Daemon

also de???nes IGMP message types that enable hosts to join and leave multicast groups, and that allow multicast routers to query one another for routing information.

Overview

The gated Routing Daemon

Overview

The gated Routing Daemon

???gated translates among several protocols, passing information within or between IP routing domains or autonomous systems. Autonomous system (AS) is used here to refer to a group of connected nodes and routers in the same administrative domain that exchange routing information via a common routing protocol.

???gated provides the system administrator ???exibility in setting up and controlling network routing. For example, gated can listen to network traf???c at speci???ed routers, determine available routes, and update local routing tables accordingly.

Deciding When to Use gated

gated is mostly used in large networks, or in small networks connected to larger wide area networks.

You must run gated on routers (gateways) to send the routing information to other routers. gated supports many routing protocols that allow routers to build and maintain dynamic routing tables. However, gated also supports RIP, which runs on end systems (systems with only one network interface) as well as on routers.

gated is useful in topologies with multiple routers and multiple paths between parts of the network. gated allows routers to exchange routing information and to change routing information dynamically to re???ect topology changes and maintain optimal routing paths.

Alternatively, you can con???gure IP routes manually with the route (1M) command. For end systems in subnets with only one router (gateway) to the Internet, manually con???guring a default route is usually more ef???cient than running gated. For more details on manually manipulating the routing tables, type man 1M route at the HP-UX prompt.

When connected to wide area networks, you can use gated to inject local routing information into the wide area network???s routing table.

Overview

The gated Routing Daemon

Routing Protocols

For routing purposes, networks and gateways are logically grouped into autonomous system (AS). Companies and organizations that want to connect to the Internet and form an AS must obtain a unique AS number from the Internet Assigned Numbers Authority (IANA).

An interior gateway protocol distributes routing information within the autonomous system. An exterior gateway protocol distributes general routing information about an autonomous system to other autonomous systems.

Dividing networks into autonomous systems keeps route changes inside the autonomous system from affecting other autonomous systems. When routes change within an autonomous system, the new information need not be propagated outside the autonomous system if it is irrelevant to gateways outside the autonomous system.

gated supports the following interior gateway protocols, as de???ned in IETF RFCs:

???Routing Information Protocol (RIP) is a common routing protocol used within an autonomous system. A de facto industry standard, it is also used by routed, a service distributed by Berkeley. RIP is not intended for use in wide area network (WAN) applications. There are currently two versions of RIP implementations: Version 1, as de???ned in RFC 1058, and Version 2, as de???ned in RFC 1388. gated supports all Version 1 features and most of the features of Version 2. The following Version 2 features are not supported: RIP management information base (MIB) route tag, and route aggregation. gated 3.5.9 supports authentication.

???Open Shortest Path First (OSPF), similar to RIP, is a routing protocol that allows routing information to be distributed between routers in an autonomous system. Each router on the network transmits a packet that describes its local links to all other routers. The distributed database is then built from the collected descriptions. If a link fails, updated information ???oods the network, allowing all routers to recalculate their routing tables at the same time. OSPF is more suitable than RIP for routing in complex networks with many routers. gated 3.0 supports most of the features of OSPF Version 2, as described in RFC 1247, except the IP type of service (TOS) routing feature. Equal cost multipath routes are limited to one hop per destination, because the HP-UX kernel supports only one gateway per route.

Overview

The gated Routing Daemon

gated supports the following exterior gateway protocols:

???The External Gateway Protocol (EGP) permits a node on the NSFNET backbone to exchange information with other backbone nodes about reaching a destination. You can use EGP to communicate routing information between autonomous systems. The EGP protocol will be obsoleted in a future release of HP-UX. Use BGP instead of the EGP protocol. BGP offers more ???exibility and requires less bandwidth than EGP.

???The Border Gateway Protocol (BGP) is intended as a replacement for EGP. BGP uses path attributes to select routes. One of the attributes that BGP can pass is the sequence of autonomous systems that must be traversed to reach a destination. gated supports BGP Versions 2, 3, and 4, as described in RFCs 1163 and 1267.

gated also supports the Router Discovery Protocol (RDP), which is neither an interior nor an exterior gateway protocol. RDP is used to inform hosts of the existence of routers to which the hosts can send

Overview

The gated Routing Daemon

packets. It is used instead of, or in addition to, a statically con???gured default router. Router discovery consists of two parts: a server part that runs on routers, and a client part that runs on hosts.

Overview

The gated Routing Daemon

This chapter describes how to con???gure mrouted and the various con???guration commands in mrouted. It also provides information on starting and verifying the mrouted installation. A description of the mrouted routing tables is also provided, along with the various multicast

Con???guring mrouted

routing support tools. This chapter discusses the following topics:

??????How to Con???gure mrouted??? on page 31

??????Starting mrouted??? on page 36

??????Verifying mrouted Operation??? on page 37

??????Displaying mrouted Routing Tables??? on page 38

??????Multicast Routing Support Tools??? on page 41

Con???guring mrouted

How to Con???gure mrouted

How to Con???gure mrouted

When the mrouted daemon starts, it automatically reads the default con???guration ???le /etc/mrouted.conf. You can override the default con???guration ???le by specifying an alternate ???le while invoking mrouted. See ???Starting mrouted??? on page 36 for more information. If you change the /etc/mrouted.conf ???le while mrouted is running, issue the following command to reread the con???guration ???le:

kill -HUP

By default, mrouted automatically con???gures itself to forward on all multicast-capable interfaces, excluding the loopback interface that has the IFF_MULTICAST ???ag set. Therefore, you do not need to explicitly con???gure mrouted, unless you need to con???gure tunnel links, change the default operating parameters, or disable multicast routing over a speci???c physical interface.

Con???guration Commands

You can de???ne the con???guration commands in the /etc/mrouted.conf con???guration ???le. mrouted supports ???ve con???guration commands: phyint, tunnel, cache_lifetime, pruning, and name. One or more options are associated with each command.

The syntax of each command is as follows:

phyint local-addr [disable] [metric m] [threshold t] [rate_lim it b]

[boundary (boundary-name|scoped-addr/mask-len)] [altnet network/mask-len]

tunnel local-addr remote-addr [metric m] [threshold t] [rate_l imit b]

[boundary (boundary-name|scoped-addr/mask-len)]

cache_lifetime ct

pruning off/on

name boundary-name scoped-addr/mask-len

phyint

Con???guring mrouted

How to Con???gure mrouted

You can use the phyint command to disable multicast routing on the physical interface identi???ed by the local IP address, local-addr (see Figure 2-1), or to associate a nondefault metric or threshold with the speci???ed physical interface. Alternatively, you can replace the local IP address, local-addr, with the interface name, such as lan0. If phyint is attached to multiple IP subnets, use the altnet option to describe each additional subnet (one altnet option for each subnet).

tunnel

You can use the tunnel command to establish a tunnel link between the local IP address, local-addr, and the remote IP address, remote-addr (see Figure 2-1). You can also use this command to associate a nondefault metric or threshold value with the tunnel. You can replace the local IP address, local-addr, with the interface name, such as lan0. Similarly, you can replace the remote IP address, remote-addr, by a host name, but only if the host name has a single IP address associated with it. Before you can use a tunnel, it must be set up in the mrouted con???guration ???les of both the mrouted routers participating in the tunnel. mrouted 3.8 does not support the srcrt option. (It provided backward compatibility with older versions of mrouted that implemented IP multicast datagram encapsulation using IP source routing.)

Con???guring mrouted

How to Con???gure mrouted

The metric is the cost, or overhead, associated with sending a datagram on the given interface or tunnel, and is used primarily to in???uence the choice of routes over which the datagram is forwarded; the larger the value, the higher the cost. You must keep metrics as small as possible, because mrouted cannot route along paths with metrics greater than 31. In general, use a metric value of 1 for all links unless you are speci???cally attempting to force traf???c to take another route. In this case, the metric of the alternate path should be the sum of the metrics on the primary path + 1. The default metric value is 1.

The threshold is the minimum IP time-to-live (TTL) required for a multicast datagram to be forwarded to a given interface or tunnel. It controls the scope of multicast datagrams. If the TTL value in the datagram is less than the threshold value, the datagram is dropped; if the TTL is greater than or equal to the threshold value, the packet is forwarded. The default threshold value is 1.

Con???guring mrouted

How to Con???gure mrouted

The TTL value of forwarded packets is only compared with the threshold value; it is not decremented by the threshold. An application that initiates the IP multicast datagram sets the TTL, and typically represents the number of subnets, or hops, the datagram has to traverse to reach its destination. Every time a multicast datagram passes through a multicast router, the TTL value is decremented by 1. HP recommends that you use the default threshold value unless you have a speci???c reason to set it otherwise.

In general, all interfaces connected to a particular subnet or tunnel should use the same metric and threshold values for that subnet or tunnel.

You can use the rate_limit option to specify a certain bandwidth in Kbits/second which is allocated to multicast traf???c. The default value is 500Kbps on tunnels and 0 (unlimited) on physical interfaces.

You can use the boundary option to con???gure an interface as an administrative boundary for the speci???ed boundary-name or scoped-addr (scoped address). You can specify more than one boundary option in the phyint and tunnel commands. Packets belonging to the scoped address, which is an IP multicast group address, are not forwarded on this interface. mask-len indicates the number of leading 1s in the mask applied (by means of a bitwise logically AND operation) to the scoped address. For example, the statement boundary 239.2.3.3/16 would result in the mask 255.255.0.0 being calculated by means of an AND operation with 239.2.3.3 to isolate the ???rst two octets, 239.2, of the scoped address. Therefore, all IP multicast addresses beginning with 239.2 will not be forwarded on the speci???ed interface.

The primary use of the boundary option is to allow concurrent use of the same IP multicast addresses on downstream subnets, without interfering with multicast broadcasts using the same IP multicast addresses on subnets that are upstream from the mrouted gateway.

The cache_lifetime value determines the amount of time that a cached multicast route remains in the kernel before timing out. This value is speci???ed in seconds and must be between 300 (5 minutes) and 86400 (24 hours). The default value is 300.

You can use the pruning off command to explicitly con???gure mrouted as a nonpruning router. When pruning is off, IP multicast datagrams are forwarded to leaf subnets of the broadcast routing tree even when

Con???guring mrouted

How to Con???gure mrouted

those leaf subnets do not contain members of the multicast destination group. Use only nonpruning mode for testing. The default mode for pruning is on.

You can use the name command to assign a name (boundary-name) to a boundary (a scoped-addr/mask-len pair) to simplify the con???guration task.

mrouted terminates if it has less than two enabled virtual interfaces (VIFs), where a VIF is either a physical multicast-capable interface or a tunnel. It logs a warning message if all the VIFs are tunnels. HP recommends that you replace such con???guration settings with more direct tunnels.

Con???guring mrouted

Starting mrouted

Starting mrouted

You can start mrouted from the HP-UX prompt or from within a shell script by issuing the following command:

/etc/mrouted [-p] [-c config_file] [-d debug_level]

The -p option disables pruning by overriding the pruning on statement within the /etc/mrouted.conf con???guration ???le. You must use this option for testing purposes only.

The -c option overrides the default con???guration ???le /etc/mrouted.conf. Use config_file to specify an alternate con???guration ???le.

The -d debug_level option speci???es the debug level. debug_level can be in the range 0 to 3. To know more about debug_level values, type man 1M mrouted at the HP-UX prompt.

By default, mrouted always writes warning and error messages to the system log daemon. You can retrieve these messages from the system log ???le, syslog.log, located in the /var/adm/syslog directory.

For convenience in sending signals, mrouted writes its pid to the

/var/tmp/mrouted.pid ???le upon startup.

Con???guring mrouted

Verifying mrouted Operation

Verifying mrouted Operation

You can use one or more of the following methods to verify mrouted operation:

???Retrieve the virtual interface table and the multicast routing table to verify if appropriate virtual interfaces (vifs) are con???gured. See ???Displaying mrouted Routing Tables??? on page 38 for information on retrieving these tables.

???Retrieve the routing cache table to verify if the routing and cache information is appropriate for your con???guration of mrouted. See ???Displaying mrouted Routing Tables??? on page 38 for information on retrieving this table.

???Examine the syslog ???le /var/adm/syslog/syslog.log for warning and error messages that indicate the status of mrouted. Upon startup, mrouted logs a startup message in the syslog ???le that indicates the mrouted version number, such as mrouted version 3.8.

???Issue the following ps (process status) command to search for the string ???mrouted???, using grep, to determine if the mrouted program is running:

ps -ef | grep mrouted

Con???guring mrouted

Displaying mrouted Routing Tables

Displaying mrouted Routing Tables

mrouted contains three routing tables: the virtual interface table, the multicast routing table, and the multicast routing cache table.

The virtual interface table displays the following topological information for each virtual interface:

???Physical and tunnel interfaces.

???The number of incoming and outgoing packets at each interface.

???The value of speci???c con???guration parameters, such as metric and threshold.

An example virtual interface table is as follows:

Con???guring mrouted

Displaying mrouted Routing Tables

peers: 36.8.0.77 (2.2)

boundaries: 239.0.1

239.1.2

pkts in: 34545433

The multicast routing table displays connectivity information for each subnet from which a multicast datagram can originate.

The multicast routing cache table is a duplicate copy of the kernel forwarding cache table. It contains the status information for multicast destination group-origin subnet pairs.

mrouted retrieves these tables by sending an appropriate signal to the mrouted daemon. mrouted responds to the following signals:

You can send signals to mrouted by issuing the HP-UX kill command at the HP-UX prompt. For example:

kill -USR1 pid

where pid is the process ID of the mrouted daemon.

For more information on the routing tables, type man 1M mrouted at the HP-UX command prompt, and see the EXAMPLE section.

Con???guring mrouted

Displaying mrouted Routing Tables

For more information on signals, type man 1M mrouted at the HP-UX command prompt, and see the Signals section.

Con???guring mrouted

Multicast Routing Support Tools

Multicast Routing Support Tools

This section describes various multicast routing support tools.

The mrinfo Tool

mrinfo is a multicast routing tool that requests con???guration information from mrouted and prints the information to the standard output. By default, mrouted prints con???guration information for its local instance. You can override the default request (the local instance of mrouted) by specifying an alternate router IP address or system name.

For more information, type man 1M mrinfo at the HP-UX command prompt.

The map-mbone Tool

map-mbone is a multicast routing tool that requests multicast router connection information from mrouted and prints the connection map information to the standard output. By default (when no alternate router address is speci???ed), the request message is sent to all the multicast routers on the local network. If map-mbone discovers new neighbor routers from the replies, it sends an identical request to those routers. This process continues till the list of new neighbors is exhausted.

For more information, type man 1M map-mbone at the HP-UX command prompt.

The netstat Tool

You can used netstat to display multicast-related information, including network statistics and multicast routing table contents.

For more information, type man 1M netstat at the HP-UX command prompt.

Con???guring mrouted

Multicast Routing Support Tools

gated handles multiple routing protocols. You can con???gure the gated daemon to perform all or any combination of the supported protocols.

Con???guring gated

The HP-UX 11i v2 operating system supports gated 3.5.9. This chapter contains information about how to con???gure gated on various routing protocols. It also describes how to specify the tracing options and route preference in gated, and discusses certain troubleshooting measures.

This chapter discusses the following topics:

??????Con???guration Overview??? on page 45

??????Con???guring the RIP Protocol??? on page 50

??????Con???guring the OSPF Protocol??? on page 60

??????Con???guring RDP??? on page 87

??????Customizing Routes??? on page 90

??????Specifying Tracing Options??? on page 92

??????Specifying Route Preference??? on page 94

??????Importing and Exporting Routes??? on page 97

??????Starting gated??? on page 99

??????Troubleshooting gated??? on page 101

For additional information on gated, type man 1M gated.conf at the HP-UX prompt.

Con???guring gated

Con???guration Overview

Con???guration Overview

Upon startup, gated reads the con???guration ???le to decide how each protocol must be used to manage routing. By default, it uses the con???guration ???le named/etc/gated.conf. Creating the con???guration ???le is usually the responsibility of the system administrator.

The con???guration ???le can include up to eight sections (called classes) of con???guration statements. You can de???ne the statements further with optional clauses. The eight classes of con???guration statements are:

???Directives ??? Directives are statements that are immediately acted upon by the gated parser.

???Trace ??? Trace statement controls gated tracing options.

???Options ??? Options statements de???ne global gated options.

???Interface ??? Interface statements de???ne router interface options.

???De???nition ??? De???nition statements identify the autonomous system that the router belongs to and martian addresses (addresses for which routing information must be ignored).

???Protocol ??? Protocol statements enable or disable gated protocols and set protocol options.

???Static ??? Static statements de???ne static routes or default routers that are installed in the kernel routing table.

???Control ??? Control statements de???ne routes that are imported to the router from other routing protocols, and paths that the router exports to other routing protocols.

For a description of each con???guration class and to determine which statements belong to which class, type man 4 gated.conf at the HP-UX prompt.

With Version 3.5.9 of gated, the two statements previously in the Trace class (tracefile and traceoptions) have been combined into a single traceoptions statement. Therefore, the tracefile statement has been eliminated. Also, some of the global options have been removed, some new global options have been added, and options have been added for some of the protocols. For details about the new syntax, type man 4 gated.conf at the HP-UX prompt.

Con???guring gated

Con???guration Overview

If you do not want to use any of the gated 3.5.9 features added at HP-UX 10.30, and do not have any tracing con???gured in your gated 3.0 /etc/gated.conf con???guration ???le, you can continue to use your 3.0 con???guration ???le with gated 3.5.9. If you do have tracing con???gured in your gated 3.0 ???le, you must run the conv_config conversion tool on the ???le so that it follows the 3.5.9 syntax (see ???Converting the Con???guration File from 3.0 to 3.5.9??? on page 48). For more information about the 3.5.9 syntax, type man 4 gated.conf at the HP-UX prompt.

To check your gated 3.0 con???guration ???le for compatibility with the 3.5.9 syntax, issue the following command at the command prompt:

gated -c [-f config_file_name]

You need to specify -f config_file_name only if the con???guration ???le you are checking is not the default ???le.

If you are still running gated 2.0, you must manually edit the /etc/gated.conf ???le so that it follows the 3.5.9 syntax. The conversion utility that was previously available to migrate from gated 2.0 to 3.0 is no longer available, and you can only use the conv_config tool when migrating from 3.0 to 3.5.9.

Con???guring gated

To con???gure gated, complete the following steps:

1.Issue the following command to create the gated con???guration ???le

/etc/gated.conf: gdc newconf

If the protocols are not explicitly speci???ed, gated assumes the following:

rip yes; ospf no;

2.Determine how you want to con???gure each routing protocol, then add the appropriate statements for each protocol to the /etc/gated.conf con???guration ???le.

See the section ???Con???guring the OSPF Protocol??? on page 60 for OSPF routing con???guration statements. RIP con???guration is described in ???Con???guring the RIP Protocol??? on page 50. For a more detailed description of the con???guration statements, type man 4 gated.conf at the HP-UX prompt.

Con???guring gated

Con???guration Overview

3.Add statements for any additional con???guration information. See ???Customizing Routes??? on page 90, ???Specifying Tracing Options??? on page 92, and ???Specifying Route Preference??? on page 94 for other con???guration options.

In particular, you may want to prevent gated from deleting interfaces from the routing table when gated does not receive routing protocol information from that interface. To do this, insert passive interface de???nitions in the interfaces statements. For example:

interfaces {

interface all passive ;

} ;

:

:

<protocol statements follow>

4.If you normally use default routes, you must con???gure a static default route in the gated con???guration ???le. If the default route is a gateway node, add the following entry to /etc/gated.conf (enter the gateway node???s IP address for gateway_IP_Address):

static {

default gateway gateway_IP_Address retain ;

} ;

The default route may be a local interface, such as in topologies that include a proxy ARP server on the local network. If the default route is a local interface, add the following entry to /etc/gated.conf:

static {

default interface local_IP_Address retain ;

} ;

The local_IP_Address is the local system???s IP address of the interface or network interface name (that is, lan0, lan1, and so on) that acts as the default route. If you use a proxy ARP server, this is the local address of the interface attached to the same network as the proxy ARP server.

See ???Customizing Routes??? on page 90 and the section covering ???Common Problems??? on page 104 in the section ???Troubleshooting gated??? on page 101 for more information.

5.To check for syntax errors in the con???guration ???le, run gated with the -c or -C option (gated exits after parsing the con???guration ???le).

Con???guring gated

Con???guration Overview

6.Set the environment variable GATED to 1 in the ???le

/etc/rc.config.d/netconf to invoke gated automatically when the system is started.

7.To start gated, reboot your system or run the following gated startup script:

/sbin/init.d/gated start

You can also start gated by executing the following command: gdc start

The following message appears: gated started, pid 25579 where

25579 is the process ID (pid) of the gated process.

Examples of gated con???guration ???les are included in the sections ???Con???guring the OSPF Protocol??? on page 60 and ???Con???guring the RIP Protocol??? on page 50. Additionally, they are also included in the

/usr/newconfig/gated/conf directory.

Converting the Con???guration File from 3.0 to 3.5.9

To convert a gated 3.0 con???guration ???le to the gated 3.5.9 syntax, complete the following steps:

Con???guring gated

Con???guration Overview

1.Retain a copy of the gated 3.0 con???guration ???le, because you cannot specify the same ???le for input and output while running the conv_config conversion tool. For example, if you are using /etc/gated.conf for 3.0, type the following command:

cp /etc/gated.conf /etc/gated.conf.30

2.Issue the following command at the HP-UX prompt:

conv_config < input_config_file_name > output_config_file where

input_config_file_name is the name of the gated 3.0 ???le you want to convert. You must specify this name, because the tool does not assume that you are converting the default ???le, /etc/gated.conf.

output_config_file is the name of the new con???guration ???le for gated 3.5.9. You must specify this name, because the tool does not assume that you are coverting the default ???le, /etc/gated.conf.

For example, to convert the gated 3.0 con???guration ???le to gated 3.5.9, issue the following command:

conv_config < /etc/gated.conf.30 > /etc/gated.conf

After running the conversion tool, you can check the new con???guration ???le for compatibility using the gated -c command. See the Note in the section ???Con???guration Overview??? on page 45 for more information.

Con???guring gated

Con???guring the RIP Protocol

Con???guring the RIP Protocol

RIP uses hopcount to determine the shortest path to a destination. Hopcount is the number of routers a packet must pass through to reach its destination. If a path is directly connected, it has the lowest hopcount of 1. If the path passes through a single router, the hopcount increases to 2. Hopcount can increase to a maximum value of 16, which is RIP???s in???nity metric, an indication that a network or node cannot be reached.

If gated encounters an unreachable node, it goes into Holddown Mode. Holddown Mode stops a node from propagating routing information until the other nodes that it is communicating with stabilize their routing information.

Hosts with only one LAN interface may use the RIP protocol with gated to passively listen to routing information when multiple routers on the LAN exist. If only one router on the LAN exists (leaving only one path off the local LAN), you can con???gure a static route to that router in the /etc/rc.config.d/net ???le, or issue the route command manually, instead of running gated.

In certain cases, you may not want the traf???c to follow a certain path, because it incurs an unacceptable cost or security risk. In these cases, gated allows you to assign a metric to each interface. This allows you to select or bypass a path, irrespective of its length or speed.

RIP Protocol Statement

The syntax of the RIP protocol statement is as follows:

rip yes|no | on|off [ { broadcast|nobroadcast ; nocheckzero ; preference preference ; defaultmetric metric ;

query authentication [none|[[simple|md5] password]] ; interface interface_list

[noripin]|[ripin] [noripout]|[ripout] [metricin metric] [metricout metric]

[version 1]|[version 2 [multicast|broadcast]] [[secondary] authentication [none|[simple|md5] password]

] ;

[interface ...]

Con???guring gated

Con???guring the RIP Protocol

trustedgateways router_list ; sourcegateways router_list ; traceoptions traceoptions ;

} ] ;

Curly braces ({}) are part of the syntax for the RIP protocol statement. Square brackets ([]) are not part of the syntax; they are used here to indicate optional parameters.

yes (or on) informs gated to enable the RIP protocol at this node and to process RIP packets coming in from other nodes. no (or off) informs gated to disable the RIP protocol at this node. If gated ???nds fewer than two network interfaces, the node listens to RIP information. If gated ???nds two or more network interfaces, the node not only listens but also broadcasts or multicasts the RIP information. If you do not specify a RIP statement in your con???guration ???le, rip on is assumed.

The following describes the various options in the RIP statement:

???broadcast speci???es that RIP packets are always generated. If the RIP protocol is enabled and more than one interface is speci???ed, broadcast is assumed. Specifying broadcast with only one interface is useful only when propagating static routes or routes learned from other protocols.

???nobroadcast speci???es that RIP packets are sent only to routers listed in the sourcegateways clause. If the RIP protocol is enabled, but only one interface is speci???ed, nobroadcast is assumed.

???nocheckzero speci???es that the RIP protocol must not check whether the reserved ???elds in the RIP packets are zero. In RIP Version 1 (as described in RFC 1058), certain reserved ???elds must be zero; however, this may vary in RIP implementations.

???preference determines the order of routes from other protocols to the same destination in the routing table. gated allows one route to a destination per protocol for each autonomous system. In case of multiple routes, the route used is determined by the value of preference.

Default: 100

Range: 0 (most preferred) ??? 255 (least preferred)

???defaultmetric is the default metric used when propagating routes learned from other protocols.

Default: 16

Con???guring gated

Con???guring the RIP Protocol

Range: 1 ??? 16

???query authentication [none|[[simple|md5] password]] speci???es the authentication, if any, that is required for query packets that do not originate from routers. If authentication consisting of only a password is required, specify simple password or password. If the required authentication consists of a key that was created with the MD5 algorithm, specify md5. Default: none.

???interface is speci???ed as one of the following (in the order of precedence): an IP address (for example, 193.2.1.36), a domain or interface name (for example, lan0 or lan1), a wildcard name (for example, lan*), or all (which refers to all interfaces). You can specify multiple interface statements with different clauses. If you specify a clause more than once, the instance with the most speci???c interface reference is used.

???noripin speci???es that gated does not process any RIP information received through the speci???ed interface. Default: ripin.

???noripout speci???es that gated does not send any RIP information through the speci???ed interface. Default: ripout.

???metricin speci???es the incoming metric for all routes propagated to this node through the speci???ed interface.

Default: kernel interface metric plus 1 (the default RIP hopcount)

???metricout speci???es the outgoing metric for all routes propagated by this node through the speci???ed interface.

Default: 0

???version 1 speci???es that RIP Version 1 packets (as de???ned in RFC 1058) are sent; RIP Version 2 packets (de???ned in RFC 1388) are sent only in response to a Version 2 poll packet. version 2 speci???es that RIP Version 2 packets are sent to the RIP multicast address or to the broadcast addresses. You can specify how the packets are sent with the multicast or broadcast clauses. version 2 multicast implies that you want to send Version 2 packets (containing subnet mask information). version 2 broadcast implies that you want to send Version 2 packets. If you do not specify a version, version 1 is assumed.

Con???guring gated

Con???guring the RIP Protocol

???[secondary] authentication [none|[simple|md5] password] speci???es the type of authentication for RIP Version 2 packets (it is ignored for Version 1 packets). secondary indicates that the secondary authentication is de???ned; otherwise, the primary authentication is de???ned. If authentication consisting of only a password is required, specify simple password or password (where password is a quoted string of 0 ??? 16 characters). If the required authentication consists of a key that was created with the MD5 algorithm, specify md5. Default: none. (If you do not specify the authentication clause, the default is primary authentication of none and no secondary authentication.

???trustedgateways provides a list of routers that provide valid RIP routing information; routing packets from other routers are ignored.

Default: all routers on the attached networks.

???sourcegateways speci???es routers to which you can send RIP routing packets. If you specify the nobroadcast clause, routing updates are sent only to routers listed in the sourcegateways clause.

???traceoptions enables tracing for the RIP protocol. See ???Specifying Tracing Options??? on page 92.

Con???guration Options

The -e and -a con???guration options help increase the RIP convergent time on the HP-UX operating system. You can set these command-line options in the /etc/gated.conf ???le under the RIP protocol statement.

The -e option speci???es route_expiry_time, which is the expiration time used by RIP to determine route aging. The minimum value is 1 second, and the maximum value is 180 seconds. The default value is 180 seconds.

Using the -a option, you can specify the route_update_time option. route_update_time is the time in seconds required by the RIP protocol to send RIP updates to other nodes on the network. The minimum value is 1 second, and the maximum value is 30 seconds. The default value is 30 seconds.

Alternatively, you can manually change the value in the /etc/gated.conf ???le. You can specify the -e and -a options either on the command line or in the con???guration ???le. Con???guration ???le options override the command-line options.

Con???guring gated

Con???guring the RIP Protocol

Simple RIP Con???guration

A simple RIP con???guration consists of RIP routers and end nodes that listen to information exchanged by the RIP routers, as shown in Figure 3-1.

Figure 3-1 and the accompanying text describe con???guration of a single end system (node A) and a RIP router (node B). The con???guration is the same for multiple end systems and RIP routers (only node B???s con???guration is shown here). This example shows only the syntax needed for a simple con???guration. A detailed description of the entire RIP protocol statement is given after this example.

A: End System on a LAN with RIP Routers

Set up the con???guration ???le /etc/gated.conf in the end system A as follows:

rip yes {

interface 121.1.0.10 version 2 multicast;

}; static {

default interface 121.1.0.10 preference 255 ;

};

Con???guring gated

Con???guring the RIP Protocol

With one interface, A can listen to RIP traf???c on the network but does not forward routing information. Routers must be multicasting RIP packets on this network for A to learn about them and update its routing table. The ???rst syntax statement enables RIP on node A???s interface (121.1.0.10) to multicast routing information. The second statement speci???es a static local default route to prevent gated from deleting it.

B: RIP Router

Set up /etc/gated.conf as follows:

rip yes {

interface all version 2 multicast ;

};

This enables the RIP protocol to multicast routing information on all interfaces.

Example of a Large RIP Con???guration

Figure 3-2 and the accompanying text describe how to con???gure gated for the RIP protocol in each node within a networked system.

B, D, and E pass routing information among themselves and update their routes accordingly. C listens to the RIP conversation between B, D, and E, and updates its routes accordingly. If both the routers D and E can provide a path to a network, but the path through router D is shorter, nodes B, C, and E use router D when routing packets to that network. If D goes down, E becomes the new router to that network for the nodes B, C, and E.

Con???guring gated

Con???guring the RIP Protocol

130.15.0.6121.1.0.92

B: Root Server

A: Cluster Node (or Isolated Node)

You need not run gated at this node, because it is on a LAN with only one router. Set a static default route to the cluster server (B) in the

/etc/rc.config.d/netconf ???le as follows:

ROUTE_DESTINATION[0]= "default"

ROUTE_GATEWAY[0]= "130.15.0.6"

ROUTE_COUNT[0]= "1"

Con???guring gated

Con???guring the RIP Protocol

B: Cluster (or Root) Server Node

Run gated to get routing information about the 121.0.0.0 network. Set up /etc/gated.conf as follows:

interfaces {

interface 130.15.0.6 121.1.0.92 passive ;

};

rip yes {

interface 130.15.0.6 noripout ; interface 121.1.0.92 version 2 multicast;

}; static {

default gateway 121.1.0.2 preference 255 ;

};

In the previous example, setting rip to yes is similar to setting rip to broadcast. Both the arguments inform the node to send out RIP packets, because the node has at least two interfaces. To reduce traf???c on the 130.15.0.0 LAN, use the noripout option on this interface. This prevents RIP from sending packets on the 130.15.0.0 network.

To isolate the 130.15.0.0 LAN, use the following:

export proto rip interface 121.1.0.92 { proto direct {

130.15.0.0 restrict ;

};

};

To further isolate the LAN from the 121.1.0.0 LAN, do not specify any static routes that specify that you can reach the LAN through B. See ???Importing and Exporting Routes??? on page 97 for more information.

Always specify the passive option with the interface???s IP address. It informs gated to maintain the routes even if no other nodes on the 121.0.0.0 network are using RIP. Without this clause, gated changes the preference of the route to the interface if it does not receive routing information for that interface. The static default route adds the speci???ed default to the kernel routing table. Setting the preference to 255 replaces this route whenever another default route is learned from one of the protocols.

C: End System on a LAN with RIP Routers

Set up /etc/gated.conf as follows:

Con???guring gated

Con???guring the RIP Protocol

rip yes {

interface 121.1.0.10 version 2 multicast;

}; static {

default interface 121.1.0.10 preference 255 ;

};

With one interface, C can listen to RIP traf???c on the network but does not forward routing information. Routers must be multicasting RIP packets on this network for C to learn about them and to update its routing table.

D: Major Router

Set up /etc/gated.conf as follows:

rip yes {

interface all version 2 multicast ;

};

This runs RIP on all attached networks.

E: Major Router

Set up the con???guration ???le /etc/gated.conf as follows:

rip yes {

interface all version 2 multicast;

};

Controlling RIP Traf???c

This section describes con???guration options for RIP routing information sent by gated from the node. Use these options to hide all or part of your network from other networks or to limit network traf???c.

The RIP protocol de???nition in the /etc/gated.conf ???le contains the following two options for limiting RIP routing information exported by gated:

???The noripout clause in the interface de???nition informs gated not to send any RIP information through the listed interfaces.

???The sourcegateways clause informs gated to send RIP information directly to the speci???ed routers.

See ???RIP Protocol Statement??? on page 50 for more information about these clauses.

Con???guring gated

Con???guring the RIP Protocol

The options for limiting RIP routing information imported by gated in the RIP protocol de???nition in the /etc/gated.conf ???le are as follows:

???The noripin clause in the interface de???nition informs gated not to process RIP information received through the listed interfaces.

???The trustedgateways clause informs gated to listen to RIP information received only from the speci???ed routers.

See ???RIP Protocol Statement??? on page 50 for more information about these clauses.

You can also use the gated import and export statements to restrict and control the route information propagated from one routing protocol to another. See ???Importing and Exporting Routes??? on page 97 for more information.

Con???guring gated

Con???guring the OSPF Protocol

Con???guring the OSPF Protocol

Open Shortest Path First (OSPF) is a link-state routing protocol that distributes routing information between routers in a single autonomous system (AS). Each OSPF router transmits a packet with a description of its local links to all other OSPF routers. The distributed database is built from the collected descriptions. Using the database information, each router constructs its own routing table of shortest paths from itself to each destination in the AS.

OSPF allows you to organize routers, networks, and subnetworks within an AS into subsets called areas. An area is a grouping of logically contiguous networks and hosts. Instead of maintaining a topological database of the entire AS, routers in an area maintain the topology for only the area in which they reside. Therefore, all routers belonging to an area must be consistent in their con???guration of the area. The topology of an area is hidden from systems that are not part of the area. The creation of separate areas can help minimize overall routing traf???c in the AS. Figure 3-3 shows an example of three separate areas de???ned for an AS.

Con???guring gated

Con???guring the OSPF Protocol

Internal routers have all their directly connected networks in the same area. In Figure 3-3, routers A, B, and H are internal routers.

Routers that are connected to multiple areas are called area border routers. In Figure 3-3, routers F and G are area border routers.

Routers that connect one AS to another are called AS boundary routers. In Figure 3-3, router D is an AS boundary router.

Neighbor routers are routers that interface to a common network. OSPF uses its own Hello subprotocol to determine which routers are neighbors. In Figure 3-3, routers A, B, and C are a set of neighbor routers that interface to network 1, while routers A and F are another set of neighbor routers that interface to network 2.

Con???guring gated

Con???guring the OSPF Protocol

Multi-access networks (networks that can be accessed through two or more neighbor routers) must have one of the routers identi???ed as a designated router.

Designated routers initiate OSPF protocol functions on behalf of the network. In Figure 3-3, you can access network 1 through the neighbor routers A, B, or C; one of these routers is elected to become the designated router for network 1.

The set of routers that exchange OSPF protocol packets between areas in an autonomous system is called the backbone. In Figure 3-3, routers C, D, E, F, G, and I form an AS backbone that allows protocol packets to travel between the three areas.

OSPF routers exchange various types of link state advertisements to build their topological databases. Most link state advertisements are ???ooded (sent to every router) throughout the attached area. An exception is the link state advertisement sent out by AS boundary routers that describe routes to destinations outside the AS; these advertisements are ???ooded throughout the AS. Table 3-1 shows the various types of link state advertisements used by the OSPF protocol.

AS boundary routers exchange routing information with routers in other autonomous systems. An AS boundary router can be an area border router or an internal router. It can also be a backbone router, but

Con???guring gated

Con???guring the OSPF Protocol

it is not required that an AS boundary router be a backbone router. An AS boundary router learns about routes other than its attached AS through exchanges with other routing protocols or through con???guration information. Each AS boundary router calculates paths to destinations outside of its attached AS. It then advertises these paths to all routers in its AS.

Following are the two levels of routing in an AS:

???Intra-area routing, where the source and destination of a packet both reside in the same area. Routing is handled by internal routers.

???Inter-area routing, where the source and destination of a packet reside in different areas. Packets travel through an intra-area route from the source to an area border router, then travel an inter-area route on a backbone path between areas. Finally, they travel another intra-area route to the destination.

Planning Your OSPF Con???guration

Following is a suggested sequence of steps in planning the OSPF routing in your autonomous system:

1.If your AS exchanges routing information with other autonomous systems, you need to obtain a unique AS number from the Internet Assigned Numbers Authority.

2.Partition the AS into areas. You can partition any interconnected networks into lists of address ranges, with each address range represented as an address-mask pair. The area border routers summarize the area content for each address range and distribute the summaries to the backbone. See ???The networks Statement??? on page 66 for more information on specifying address ranges.

3.Identify the internal routers for each area. An internal router con???guration contains only one area de???nition.

4.Identify the area border routers and the areas to which they interface. The con???guration for each area border router contains multiple area de???nitions.

5.For each router, determine the interface type for each area. Router interfaces can be multicast, non-broadcast multi-access (NBMA), or point-to-point. See ???The interface Statement??? on page 67 for more information on router interfaces.

Con???guring gated

Con???guring the OSPF Protocol

6.For multi-access networks, identify a designated router. For NBMA networks, several routers can be designated router candidates. Designated routers are speci???ed in the interface de???nitions (see ???The interface Statement??? on page 67).

7.You must decide if you want to assign a cost to each interface. See ???Cost??? on page 79 for more information about costs.

8.Designate stub areas. AS external link advertisements are propagated to every router in every area in an AS, except for routers in the con???gured stub areas. See ???Stub Areas??? on page 74 for more information

9.Identify backbone routers. The router con???guration contains a backbone de???nition and a virtual link de???nition, if necessary. See ???De???ning Backbones??? on page 76 for more information

10.Determine if routing packets are authenticated for each area. See ???Authentication??? on page 77 for more information

11.Identify AS boundary routers. See ???AS External Routes (AS Boundary Routers Only)??? on page 80 for more information.

Con???guring gated

Con???guring the OSPF Protocol

The following sections explain other statements de???ned for the OSPF protocol con???guration.

De???ning Areas

Each OSPF router is associated with one or more areas. The area statement identi???es an OSPF area. The value is in the form of a dotted quad, or a number between 1 and 4294967295. To de???ne an area, you must specify the following:

???The addresses of the networks that make up the area.

???The router interfaces used to communicate with the area.

The con???guration of an area border router contains multiple area de???nitions; a different router interface is de???ned for each area.

Figure 3-4 shows an example of an area border router that is connected to area 0.0.0.1 through interface 193.2.1.33 and to area 0.0.0.2 through interface 193.2.1.17.

Area

to Network A 193.2.1.33 Border 193.2.1.17to Network B Router

The following is an example of the area de???nitions in the router???s

/etc/gated.conf ???le:

ospf yes {

area 0.0.0.1 {

interface 193.2.1.33 {

...

};

};

area 0.0.0.2 { interface 193.2.1.17 {

...

} ;

};

} ;

Con???guring gated

Con???guring the OSPF Protocol

You can de???ne various characteristics for an area and interfaces. The following sections describe the con???guration statements that you can use in de???ning an area.

The networks Statement

The networks statement de???nes the address ranges that forms an OSPF area. This de???nition applies only to area border routers, where multiple areas are speci???ed, and is required only if you need to compress a number of subnets using a network mask.

A network address followed by a hexadecimal bit mask speci???es an IP address range in the network statement. For example, the following address range begins with the network address 193.2.1.16 and includes the ???rst 15 addresses in that network (193.2.1.17 through 193.2.1.31):

193.2.1.16 mask 0xfffffff0

You can specify many separate networks in an address range. Area border routers advertise a single route for each address range.

Figure 3-5 shows an example of a router that is connected to area 0.0.0.1 through the interface 193.2.1.33. The attached network consists of addresses 193.2.1.33 through 193.2.1.47. The other network in the area consists of addresses 193.2.1.17 through 193.2.1.31.

Area 0.0.0.1

193.2.1.33 Router A

Con???guring gated

Con???guring the OSPF Protocol

The following is an example of the network de???nition in the Router A???s

/etc/gated.conf ???le:

ospf yes

area 0.0.0.1 networks {

193.2.1.16 mask 0xfffffff0 ; 193.2.1.32 mask 0xfffffff0 ; } ;

interface 193.2.1.33 {

...

} ;

} ;

...

The interface Statement

The interface statement in the OSPF protocol de???nition speci???es the interface to use while communicating with the speci???ed networks. You can specify the interface with an address (for example, 193.2.1.36), a domain or interface name (for example, lan0 or lan1), a wild card name (for example, lan*), or all (the order of precedence is address, name, wild card name, all). You can specify multiple interface statements using different clauses. If you specify a clause more than once, the instance with the most speci???c interface reference is used.

You can specify the cost clause optionally to de???ne a cost of sending a packet on the interface. This cost is advertised as the link cost for this interface. See ???Cost??? on page 79 for more information on setting interface costs.

You can also enable or disable the interface de???nition. If you do not explicitly specify disable, an interface de???nition is enabled by default.

OSPF supports the following types of network interfaces:

???A multicast (or broadcast) network is a network that supports two or more attached routers and allows a single message to be addressed to a set of network nodes at the same time. An example of a multicast network is an Ethernet LAN.

???A non-broadcast multi-access (NBMA) network is a network that supports multiple attached routers, but does not support broadcasting of messages. An example of an NBMA network is an X.25 PDN.

Con???guring gated

Con???guring the OSPF Protocol

???A point-to-point network is a network that joins a single pair of routers. An example of a point-to-point network is a 56-KB serial line.

The following sections describe each type of interface.

Multicast Interfaces On multicast networks, an OSPF router dynamically detects its neighbor routers through the OSPF Hello message. The following statements are de???ned for a multicast interface:

???retransmitinterval is the number of seconds between retransmission of link states, database descriptions, and link state request packets. This value must exceed the expected round-trip delay between any two routers in the network. A sample value for a LAN is 5 seconds.

Default: None (you must specify a value)

Range: Integer between 0 ??? 65535

???transitdelay is the number of seconds to transmit a Link State Update Packet over this interface. This value must take into account the transmission and propagation delays for the interface. It must be greater than 0. A sample value for a LAN is 1 second.

Default: None (you must specify a value)

Range: Integer between 1 ??? 65535

???priority speci???es the priority of the router to be the designated router. You must con???gure this value only for interfaces to multi-access networks. This value speci???es the priority of the router to be the designated router. When two routers attached to a network attempt to be the designated router, the one with the higher router priority value takes precedence.

Default: None (you must specify a value for multi-access networks)

Range: 8-bit unsigned integer between 0 ??? 255. 0 means that the router is ineligible to become a designated router on the attached network.

???hellointerval speci???es the time interval (in seconds) for the transmission of OSPF Hello packets. Smaller intervals ensure that changes in network topology are detected faster. A sample value for an X.25 network is 30 seconds. A sample value for a LAN is 10 seconds.

Con???guring gated

Con???guring the OSPF Protocol

The following is an example of the multicast interface de???nition in the router???s /etc/gated.conf ???le:

interface 193.2.1.35 cost 5 { enable ;

priority 15 ; hellointerval 5 ; routerdeadinterval 20 ; retransmitinterval 10 ;

} ;

Non-Broadcast Multi-Access (NBMA) Interface On NBMA networks, you must supply the con???guration information, including the routers that are attached to the network, so that the OSPF???s Hello protocol communicates with neighbor routers. An NBMA interface de???nition applies to both X.25 network interfaces and systems that do not support IP multicasting. You can de???ne an NBMA interface using the multicast interface statements, with the following additions:

???You must specify the clause nonbroadcast in the interface statement.

???pollinterval speci???es a rate at which hellos are sent when a neighboring router becomes inactive (a router is considered inactive when hellos are not received from the router for the amount of time

Con???guring gated

Con???guring the OSPF Protocol

speci???ed by the routerdeadinterval de???nition). The value of pollinterval must be larger than the value of hellointerval. A sample value for an X.25 network is 2 minutes.

Default: None (you must specify a value)

Range: 0 ??? 255

???routers specify the list of routers attached to the non-broadcast network. Routers are de???ned by their IP interface addresses. You must de???ne the routers that are eligible to be designated routers as eligible.

Figure 3-7 shows an example of a router (A) that is connected to an NBMA network through the interface 193.2.1.35. Two other routers are also attached to the network: router B is connected through the interface 193.2.1.33 and C is connected through the interface 193.2.1.46. B and C are eligible to be designated routers.

Router

A

The following is an example of the non-broadcast interface de???nition in router A???s /etc/gated.conf ???le:

Con???guring gated

Con???guring the OSPF Protocol

interface 193.2.1.35 nonbroadcast cost 5 { routers {

193.2.1.33 eligible ;

193.2.1.46 eligible ;

};

priority 15 ; hellointerval 5 ; routerdeadinterval 20 ; retransmitinterval 10 ; pollinterval 20 ;

} ;

Point-to-Point Interfaces On point-to-point networks, an OSPF router dynamically detects its neighbor router by sending OSPF Hello packets. The following statements are de???ned for a point-to-point interface:

???retransmitinterval is the time interval (in seconds) between the retransmission of link states, database descriptions, and link state request packets. This value must exceed the expected round-trip delay between any two routers in the network. A sample value for a LAN is 5 seconds.

Default: None (you must specify a value)

Range: 0 ??? 65535

???hellointerval speci???es the time interval (in seconds) between transmission of OSPF Hello packets. Smaller intervals ensure that changes in network topology are detected faster. A sample value for an X.25 network is 30 seconds. A sample value for a LAN is 10 seconds.

Default: None (you must specify a value)

Range: 0 ??? 255

Con???guring gated

Con???guring the OSPF Protocol

???routerdeadinterval speci???es the time interval (in seconds) for which the Hello packets are not received from a router before it is considered down or inactive by its neighbors. This value must be a multiple of the hellointerval value.

Default: None (you must specify a value)

Range: 0 ??? 65535

You can de???ne a point-to-point interface with or without a nonbroadcast clause. If you specify the nonbroadcast clause, then you must de???ne the pollinterval statement.

???pollinterval speci???es a rate at which hellos are sent when a neighboring router becomes inactive (a router is considered inactive when hellos have not been received from the router for the amount of time speci???ed by the routerdeadinterval de???nition). The value of pollinterval must be larger than the value of hellointerval. A sample value for an X.25 network is 2 minutes.

Default: None (you must specify a value)

Range: 0 ??? 255

If the device at the other end of the point-to-point network is not an OSPF router, you can prevent sending Hello packets to that OSPF router using the stubhosts statement. stubhosts speci???es the IP address or domain name of the non-OSPF host. The cost of sending a packet to the host must also be speci???ed (in most cases, the host has only a single connection to the network, so the cost con???gured has no effect on routing).

Con???guring gated

Con???guring the OSPF Protocol

Figure 3-8 shows an example of a router (A) that is connected to a non-broadcast, point-to-point network through interface 193.2.1.1.

The following is an example of the interface de???nition in router A???s

/etc/gated.conf ???le:

interface 193.2.1.1 nonbroadcast cost 5 { hellointerval 30 ; routerdeadinterval 30 ; retransmitinterval 30 ; pollinterval 30 ;

} ;

If the router A is connected to a multicast, point-to-point network, you must omit the nonbroadcast clause and the pollinterval statement.

Stub Areas

By default, AS external link advertisements (routes to destinations outside the AS) are propagated to every router in every area in the AS. You can con???gure certain OSPF areas as stub areas. AS external link advertisements are not ???ooded through stub areas. This reduces the size of the topology database that must be maintained by internal routers in the stub area and reduces the protocol traf???c through the area. For example, if all the inter-area traf???c for an area must go through a single router, then it is not necessary for all routers in the area to receive inter-area routing information.

An area border router advertises a default route in the stub area as the summary of all the IP destinations that are reachable outside the AS. Summary link advertisements (routes to destinations outside the area but within the AS) are still sent into the stub area.

The stub statement speci???es that the area is a stub area. You can optionally de???ne a cost clause to specify the cost associated with the default route that is advertised in the stub area.

Con???guring gated

Con???guring the OSPF Protocol

Figure 3-9 shows an example of an area border router that is connected to area 0.0.0.2 through interface 193.2.1.20. Because all traf???c in and out of the area 0.0.0.2 must pass through router A, it is not necessary for the area???s internal routers, such as router B, to receive inter-area routing information.

The following is an example of the stub area de???nition in the router???s

/etc/gated.conf ???le:

OSPF yes {

area 0.0.0.2 { stub cost 5 ; networks {

193.2.1.16 mask 0xfffffff0 ;

};

interface 193.2.1.20 nonbroadcast cost 5 { enable ;

routers {

193.2.1.17eligible ;

};

priority 5 ; hellointerval 5 ; routerdeadinterval 20 ; retransmitinterval 10 ; pollinterval 20 ;

} ; } ;

};

Con???guring gated

Con???guring the OSPF Protocol

De???ning Backbones

The OSPF backbone distributes routing information between areas. You can de???ne backbones with the same statements and clauses as areas. You need not de???ne the stub statement for a backbone. The backbone statement is used to de???ne a router as a backbone router. If an OSPF internal or area boarder router is also a backbone router, the backbone statement must follow the area statements in the /etc/gated.conf ???le. Whenever you con???gure an area border router (a router connected to multiple areas), you must provide the backbone.

Figure 3-10 shows an example of two area border routers that form part of a backbone. Router A has interfaces to both area 0.0.0.1 and area 0.0.0.2, while router B has interfaces to areas 0.0.0.3 and 0.0.0.4. Router A is connected to router B through interface 15.13.115.156.

Figure 3-10 Backbone Con???guration Example

The following is an example of the backbone router de???nition in router A???s /etc/gated.conf ???le:

Con???guring gated

Con???guring the OSPF Protocol

backbone {

interface 15.13.115.156 { enable ;

transitdelay 20 ; priority 20 ; hellointerval 30 ; routerdeadinterval 120 ; retransmitinterval 60 ;

} ;

};

If the router is directly attached via a point-to-point interface to a host that is not running OSPF, you can prevent sending OSPF Hello packets to the host. Do this by specifying the subhost statement with the host???s address. You can optionally de???ne the cost.

Authentication

The OSPF protocol allows you to authenticate packets containing routing information. You can con???gure the authentication on a per-area basis; You can use different authentication methods in different areas.

gated supports a simple password authentication method. You can also choose to have no authentication. You can use the authtype statement to de???ne the authentication method used for the area. 0 or none speci???es that routing exchanges in the area are not authenticated. 1 or simple speci???es that network passwords of up to 64 bits (8 characters) are used to authenticate packets received from routers in the area.

In the simple password authentication method, all routers that interface to a given network use the same password. The password is de???ned by the authkey statement in the router???s interface de???nition. If you do not con???gure a router with the same password as other routers in the network, other networks discard the router???s packets. The password is

Con???guring gated

Con???guring the OSPF Protocol

con???gured on a per-interface basis. If a router has interfaces to more than one network, different passwords can be con???gured. This is illustrated in Figure 3-11.

Figure 3-11 Simple Password Authentication

A

B

C

The following example shows an authtype statement that enables a simple password authentication for the routers in the area and an authkey statement in the interface de???nition that de???nes a password (travis) to validate protocol packets received by the router:

area 0.0.0.1 { authtype simple ; networks {

193.2.1.16 mask 0xfffffff0 ; 193.2.1.32 mask 0xfffffff0 ; } ;

interface 193.2.1.35 nonbroadcast cost 5 { routers {

193.2.1.33 eligible ;

193.2.1.46 eligible ;

};

priority 15 ; enable ; hellointerval 5 ;

routerdeadinterval 20 ;

Con???guring gated

Con???guring the OSPF Protocol

retransmitinterval 10 ; pollinterval 20 ; authkey " travis " ;

} ;

} ;

Cost

The outbound side of each router interface is associated with a con???gurable cost. Lower cost interfaces are more likely to be used in forwarding data traf???c. Cost values are assigned at the discretion of the network or system administrator. While the value is arbitrary, it must be a function of throughput or capacity of the interface: the higher the value, the lower the throughput or capacity. Thus, the interfaces with the highest throughput or capacity must be assigned lower cost values than other interfaces. Interfaces from networks to routers have a cost of 0.

Figure 3-12 shows an example network where costs are speci???ed for each interface.

Figure 3-12 Cost Con???guration Example

Con???guring gated

Con???guring the OSPF Protocol

In Figure 3-12, there are two possible packet routes between nodes A and D: one route goes through node B and the other route goes through node C. The cost of each route is calculated as follows:

Node A to node B and node B to node D: 5+5 = 10

Node A to node C and node C to node D: 5+10 = 15

The lowest cost OSPF path between nodes A and D is therefore through node B. However, packets are rerouted through node C if there is a link failure between node B and LAN 2.

You can optionally de???ne cost in the following places in the /etc/gated.conf ???le:

???In a defaults statement in the OSPF protocol con???guration, which applies only to AS boundary routers. This cost de???nition applies to routes to destinations outside the AS. These routes may have been derived from other routing protocols, such as EGP. See ???AS External Routes (AS Boundary Routers Only)??? on page 80 for more information.

???In the export statement in the Control class in the /etc/gated.conf ???le, which applies only to AS boundary routers. This cost de???nition applies to routes that are exported from the AS boundary router to routers in other autonomous systems.

???In the stub area de???nition of the OSPF protocol con???guration. This cost de???nition speci???es the cost of the default summary link that is advertised in the area.

???In the stubhosts de???nition of the OSPF protocol con???guration. This cost de???nition speci???es the cost of a point-to-point interface between the router and a non-OSPF host.

???In the subhosts de???nition of the OSPF protocol con???guration. This cost de???nition speci???es the cost of a point-to-point interface between the backbone router and a non-OSPF host.

AS External Routes (AS Boundary Routers Only)

AS external (ASE) routes are paths to destinations that are outside the AS. Most ASE routes are routes to speci???c destinations. AS boundary routers specify the ASE routes through another routing protocol, such as EGP, or through con???gured routes.

Con???guring gated

Con???guring the OSPF Protocol

gated supports the use of route information from other autonomous systems that use other routing protocols, such as EGP. AS boundary routers send AS external link advertisements and ???ood the AS with advertisements (with the exception of con???gured stub areas). A single AS external link advertisement is sent for each external route that the AS boundary router has learned about.

Externally de???ned routing information and OSPF routing information are maintained separately. In addition, you can tag the externally de???ned routing information, to identify and store the source of the information along with the route information.

Statements in the Control class of the /etc/gated.conf ???le control the importing of routes from routing protocols to a gated forwarding table and the exporting of routes from the gated forwarding table. See ???Importing and Exporting Routes??? on page 97 for more information.

You must specify the defaults statements in the OSPF protocol con???guration only for AS boundary routers. These statements specify how external routing information is handled by the OSPF protocol. You can de???ne the following in the defaults statements:

???preference speci???es the preference value given to the ASE routes imported from other autonomous systems. The preference value determines the order of routes to the same destination in the routing table. gated allows one route to a destination per protocol for each AS. In case of multiple routes, the route used is determined by the lowest preference value (see ???Specifying Route Preference??? on page 94 for more information). If a preference value is not speci???ed, ASE routes are imported with a preference of 150.

Default: 150

Range: 0 (most preferred) ??? 255 (least preferred)

???cost speci???es the cost associated with an OSPF route that is exported to other AS boundary routers.

Default: 0

Range: 0 ??? 65535

???tag speci???es an OSPF tag placed on all routes exported by gated into OSPF. You can tag each external route by the AS boundary router to identify the source of the routing information. The tag

Con???guring gated

Con???guring the OSPF Protocol

value can be an unsigned 31-bit number. You can also specify tag as as_tag, where as_tag is an unsigned 12-bit number that is automatically assigned.

???type determines how ASE routes imported into OSPF are treated. Type 1 routes must be routes from internal gateway protocols with external metrics that are directly comparable to OSPF metrics.

When OSPF selects a route, OSPF uses the type 1 route???s external metric and adds the OSPF internal cost to the AS border router. Type 2 routes must be routes from external gateway protocols with metrics that are not comparable to OSPF metrics. When OSPF selects a route, OSPF ignores a type 2 route???s metric and uses only the OSPF internal cost to the AS border router.

Default: 1

???exportlimit speci???es the rate at which ASE routes are imported into the gated routing table for each exportinterval.

Default: 100 (ASE routes)

Range: 0 ??? 65535

???exportinterval speci???es the interval (in seconds) between ASE exports into OSPF.

Default: 1 (second)

Range: 0 ??? 2147483647

Con???guring gated

Con???guring the OSPF Protocol

Sample OSPF Con???guration

Figure 3-13 shows an example of two areas. Area 1 is a non-stub area, while area 2 is con???gured as a stub area. Node B is an area border router between the two areas.

Figure 3-13 OSPF Sample Con???guration

Area 1 (Non-Stub)

A

193.2.1.35

LAN 1 193.2.1.32

LAN 2 193.2.1.16

193.2.1.20

C

Area 2 (Stub)

A: Internal Router (Non-Stub Area)

Set up /etc/gated.conf as follows:

Con???guring gated

Con???guring the OSPF Protocol

# Router A Configuration (non-stub area) OSPF yes {

area 0.0.0.1 {

interface 193.2.1.35 cost 5 { priority 5 ;

enable ; hellointerval 5 ; routerdeadinterval 20 ; retransmitinterval 10 ;

} ; } ;

};

The con???guration for the internal router A is for a multicast interface. For an NBMA interface, you can set the con???guration in

/etc/gated.conf as follows:

# Router A Configuration (non-stub area) OSPF yes {

area 0.0.0.1 {

interface 193.2.1.35 nonbroadcast cost 5 { routers {

193.2.1.33 eligible ;

} ;

priority 5 ; enable ; hellointerval 5 ;

routerdeadinterval 20 ; retransmitinterval 10 ; pollinterval 20 ;

} ; } ;

};

B: Area Border Router

Set up /etc/gated.conf as follows:

OSPF yes { defaults {

cost 5 ;

Con???guring gated

Con???guring the OSPF Protocol

} ;

area 0.0.0.1 {

interface 193.2.1.33 cost 5 { priority 15 ;

enable ; hellointerval 5 ; routerdeadinterval 20 ; retransmitinterval 10 ;

} ;

} ;

area 0.0.0.2 {

interface 193.2.1.17 cost 5 { priority 15 ;

enable ; hellointerval 5 ; routerdeadinterval 20 ; retransmitinterval 10 ;

} ;

};

backbone {

interface 15.13.115.156 cost 5 { enable ;

priority 10 ; hellointerval 5 ; routerdeadinterval 20 ; retransmitinterval 10 ;

} ;

};

};

C: Internal Router (Stub Area)

Set up /etc/gated.conf as follows:

OSPF yes {

area 0.0.0.2 { stub cost 5 ;

interface 193.2.1.20 cost 5 { priority 5 ;

enable ; hellointerval 5 ; routerdeadinterval 20 ; retransmitinterval 10 ;

} ; } ;

};

Con???guring gated

Con???guring the OSPF Protocol

The routing table on node A contains routes to 193.2.1.32 and 193.2.1.16. The routing table on node C in the stub area contains routes only to LAN 1 and a default router.

Accessing the OSPF MIB

HP???s gated also provides ospfagt, an OSPF Simple Management Network Protocol (SNMP) subagent that supports the OSPF MIB (Management Information Base) (see RFC 1253). The ospfagt subagent works with the HP SNMP Agent, snmpdm. If you use an SNMP manager utility to manage your network, such as HP???s OpenView Network Node Manager, you can also use HP???s OSPF SNMP subagent.

To start ospfagt automatically during system bootup, set the environment variable OSPFMIB to 1 in the ???le

/etc/rc.config.d/netdaemons.

To manually start ospfagt, type the following command at the command prompt:

/usr/sbin/ospfagt

gated must be running before ospfagt is started. Both gated and ospfagt must be running to retrieve OSPF MIB objects.

To load the OSPF MIB, select Load/Unload SNMP:MIBS ... from the

Options menu of OpenView.

Con???guring gated

Con???guring RDP

Con???guring RDP

You can use Router Discovery Protocol (RDP), a standard protocol, to inform hosts of the presence of routers to which they can send packets. You can also use RDP instead of host wiretapping routing protocols (for example, RIP). It is used instead of, or in addition to, having statically con???gured default routes in hosts.

RDP consists of two portions: the server portion, which runs on routers, and the client portion, which runs on hosts. gated treats these portions as separate protocols; therefore, you can enable only one of them at a time. These portions are described in detail in the subsequent sections.

For a description of the RDP con???guration statements, type man 4 gated.conf at the HP-UX prompt.

RDP Server

The RDP server runs on routers, and announces the routers??? existence to hosts periodically by multicasting or broadcasting a router advertisement. The advertisement is sent over an RDP server enabled physical interface. Each router advertisement contains a list of all addresses on a physical interface and their preference for being used as a default router. You can con???gure the length of time (the lifetime) for which addresses must remain on the list.

At ???rst, router advertisements occur every few seconds, and then, they start occurring few minutes. You can con???gure the minimum and maximum intervals for router advertisements to occur. Also, a host can send a router solicitation, requesting an advertisement. The router responds with a unicast router advertisement unless a multicast or broadcast advertisement is due to occur.

On hosts that support IP multicasting, router advertisements are sent by default to the all-hosts mulicast address 224.0.0.1. You can also con???guration RDP to use broadcasting to send router advertisements. This is useful when a particular host does not support IP multicasting, or when one or more hosts on an attached network do not support IP multicasting. If router advertisements are sent to the all-hosts multicast address, or if an interface is con???gured for the limited-broadcast address 255.255.255.255, the advertisements contain all the IP addresses

Con???guring gated

Con???guring RDP

con???gured on the physical interface. If advertisements are sent to a net or subnet broadcast, only that network???s or subnet???s address is included in the advertisement.

An example of the routerdiscovery server statement is as follows:

routerdiscovery server yes { interface lan1 lan2 maxadvinterval 5 ;

address 193.2.1.17 193.2.1.33 193.2.1.46 broadcast

preference 50 ;

} ;

In the example, the server is enabled on the physical interfaces lan1 and lan2, and the IP addresses 193.2.1.17, 193.2.1.33, and 193.2.1.46 are included in all the router advertisements. Also, the addresses have a preference of 50.

RDP Client

The RDP client runs on hosts, listening for router advertisements over the all-hosts multicast address 224.0.0.1 (if it supports IP multicasting) or on the physical interface???s broadcast address (if the host does not support multicasting). When a host starts up or is recon???gured, it sends certain router solicitations requesting advertisements. When it sends the solicitations, it sends them to the all-routers multicast address 224.0.0.2 or to the interface???s broadcast address (if multicasting is not supported).

When the RDP client receives a router advertisement, the host installs a default route to each of the addresses listed in the advertisement. If the advertisement has a preference of ineligible (that is, the addresses in the advertisement are not eligible to be the default route for any hosts), or if the addresses are not on an attached physical interface, the route is marked as unusable but is still retained. If the preference is usable, then that route is among the routes considered. The route with the highest preference is used. If more than one route with the same preference is received, the one with the lowest IP address is used. The default routes are not exportable to other protocols.

If an RDP client receives a router advertisement with a zero lifetime (that is, the addresses in the advertisement are no longer valid), the host deletes all the routes with next-hop addresses learned from that router.

Con???guring gated

Con???guring RDP

The host also deletes any routes learned from ICMP redirects pointing to the invalid addresses. Also, if a router advertisement is not received before the addresses listed by the host becomes invalid (that is, before its lifetime expires), the routes learned from that router are deleted by the host.

An example of the routerdiscovery client statement is as follows:

routerdiscovery client yes { preference 50 ; interface lan0 broadcast ;

} ;

In the example, the client is enabled on physical interface lan0, and the default routes are given a preference of 50.

A simple example of an RDP server and two RDP clients is shown in

Figure 3-14.

Figure 3-14 RDP Server and Clients Example

Con???guring gated

Customizing Routes

Customizing Routes

gated maintains the routing table in user space, and synchronizes this table with the kernel routing table. This section describes statements for setting up customized routes in the Static class of the gated con???guration ???le, /etc/gated.conf. You can use these statements to specify default routers, static routes, passive interfaces, and routing metrics for interfaces.

Specifying a Default Router

A static route provides a speci???c destination for network packets. The static route is a network address or a host address through a router. This route is installed in the kernel???s routing table. The following is an example of a static route for the default route:

static {

default gateway 15.13.114.196 retain ; } ;

The retain quali???er ensures that the entry is not deleted when gated exists.

Installing Static Routes

The static statement speci???es a router or an interface in the kernel routing tables. The following is an example of a static route:

static {

193.2.1.32 mask 0xfffffff0 gateway 193.2.1.30 preference 8 retain ;

} ;

If you specify an export statement for the default route, the route is passed on to other routers. If you specify only the static statement and not an export statement, then the default route is not passed on as a route to other routers. This is considered a passive default route, and is used only by the host where this gated is running. The retain clause retains the route in the kernel even after gated shuts down.

Con???guring gated

Customizing Routes

Setting Interface States

gated times out routes that pass through interfaces not receiving any RIP, OSPF, or BGP packets. The passive clause in the interface statement of the Static class prevents gated from changing the preference of a route to the interface if routing information is not received for the interface. HP recommends that you use the passive clause for all interfaces.

Con???guring gated

Specifying Tracing Options

Con???guring gated

Specifying Route Preference

Specifying Route Preference

gated maintains a routing table that consists of the route information learned from OSPF and from other active routing protocols, such as RIP or EGP. You can also con???gure static routes in the /etc/gated.conf ???le with one or more static clauses (see ???Installing Static Routes??? on

page 90 for more information).

The gated routing pool can therefore contain multiple routes to a single destination. When multiple routes exist, the route chosen by gated is determined by the following (in order of precedence):

???The preference value associated with the route. The preference value is a number in the range from 0 (most preferred) to 255 (least preferred). Routes from different sources have different default preference values. For example, OSPF routes within a given AS have a preference value of 10. Table 3-3 shows the default preference values of various types of routes.

???If multiple routes use the same protocol and have the same preference value, the route with the lowest metric or cost is chosen.

???If metric or cost is the same, the router with the lowest IP address is chosen.

You can de???ne preference in the /etc/gated.conf ???le con???guration ???le in the following instances:

???In the static route de???nition in the Static class. This preference de???nition sets the preference for static routes. (See ???Customizing Routes??? on page 90 for more information.) If this option is not set, the preference values for static routes is 60.

???In the interface statement options in the Interface class. This preference de???nition sets the preference for routes to this interface. If this option is not set, the preference value is 0. For more information, type man 4 gated.conf at the HP-UX prompt.

Con???guring gated

Specifying Route Preference

???In a defaults statement in the OSPF protocol con???guration. This preference de???nition speci???es the preference value of ASE routes that are imported into OSPF. See ???AS External Routes (AS Boundary Routers Only)??? on page 80 for more information. ASE routes are imported into OSPF with a default preference of 150.

???In an import statement in the Control class of the /etc/gated.conf ???le. This preference de???nition overrides any preference de???ned in the defaults section of the OSPF protocol con???guration. See ???AS External Routes (AS Boundary Routers Only)??? on page 80 and ???Importing and Exporting Routes??? on page 97 for more information.

Con???guring gated

Importing and Exporting Routes

Importing and Exporting Routes

You can propagate routes from one routing protocol to another using the import and export control statements. Routes are imported into a gated forwarding table and exported out to the routing protocols.

For more information on import and export statements, type man 4 gated.conf at the HP-UX prompt.

The import Statement

import statements restrict or control routes that are imported to the gated forwarding table. When routes are imported to the gated forwarding table, you can export them to the routing protocols. You can use import statements to perform the following tasks:

???Prevent routes from being imported into the gated forwarding table by using a restrict clause.

???Assign a preference value to use when comparing a route with other routes from other protocols. The route with the lowest preference is installed in the gated forwarding table. The individual protocols con???gure the default preferences.

The format of the import statement varies depending on the protocol from which you are importing routes.

With OSPF, you can apply import statements only to OSPF ASE routes. All OSPF intra-area and inter-area routes are imported into the gated forwarding table with an assigned preference of 10.

The export Statement

export statements determine the routes that are exported from the gated forwarding table to the routing protocols. You can also restrict the routes that are exported and assign metrics (values used for route selection) to them. These metrics are applied only after the routes are exported.

The format of the export statement varies depending on the original protocol used to build the routes that you are exporting, and the protocol to which you are exporting routes.

Con???guring gated

Importing and Exporting Routes

Examples of import and export Statements

The following import statement imports a BGP route for network 195.1.1 to the gated forwarding table with a preference of 15:

import proto bgp as 1 {

195.1.1 mask 0xffffff00 preference 15;

};

The following export statement exports to OSPF the ASE route that was imported to the gated forwarding table in the previous example. The route was originally built by BGP and the destination of the route is network 195.1.1.

export proto ospfase type 1 /* Export an ASE route to OSPF */ proto bgp as 1 {/*route came from BGP and AS 1*/ 195.1.1 ; /* the route is to network 195.1.1 */

};

};

Con???guring gated

Starting gated

Starting gated

To start gated, complete the following steps:

1. Set the environment variable GATED to 1 in the ???le /etc/rc.config.d/netconf to start gated automatically upon system startup.

2. Reboot your system, or issue the following command to run the gated startup script:

/sbin/init.d/gated start

Con???guring gated

Starting gated

Verifying That gated Is Running

Issue the following command to determine if gated is running:

/usr/bin/ps -ef | /usr/bin/grep gated

This command reports the process identi???cation (PID), current time, and the command invoked (gated). Following is an example output:

daemon 4484 1 0 Feb 18 ? 0:00 gated

You can also check if gated is running by issuing the following command:

gdc running

The following message appears to indicate that gated is running:

gdc is running (pid 1312)

If gated is not running, the following message appears:

gated is not running

Con???guring gated

Troubleshooting gated

Troubleshooting gated

This section describes the following techniques for troubleshooting gated and some common problems encountered with gated operation:

??????Checking for Syntax Errors in the Con???guration File??? on page 101

??????Tracing gated Activity??? on page 101

??????Operational User Interface for gated ??? gdc??? on page 102

??????The gated Routing Table??? on page 103

??????The ripquery Tool??? on page 103

??????The ospf_monitor Tool??? on page 103

??????Common Problems??? on page 104

Checking for Syntax Errors in the Con???guration File

After creating or modifying a gated con???guration ???le, you must start gated from the command line with the -C option. This option parses the the con???guration ???le for syntax errors.

Tracing gated Activity

gated prints information about its activity in the form of tracing output. This information includes routes that gated reads, adds, and deletes from the kernel routing table, as well as packets sent and received.

You can specify tracing either with the gated -t command-line option or with the traceoptions statement in the /etc/gated.conf ???le. Using any of the following combinations, you can determine where the tracing output is printed and whether tracing is performed:

???If you specify trace options and a trace ???le, tracing output is printed to the log ???le.

???If you specify trace options but do not specify a trace ???le, tracing output is printed on the display where gated was started.

???If you specify a trace ???le but do not specify any trace options, no tracing takes place.

Operational User Interface for gated ??? gdc

gdc provides a user-oriented interface for the operation of gated. It provides the following functions:

???Starting and stopping gated.

???Delivery of signals to manipulate gated.

???Maintenance and checking the gated con???guration ???le for syntax.

???Production and removal of state dumps and core dumps.

Con???guring gated

Troubleshooting gated

gdc determines the state of gated and produces a reliable exit status during errors, which is useful in shell scripts that manipulate gated. The syslogd facility is used to log all the commands and error messages generated during gdc operation. gated uses these log messages to provide an audit trail of operations performed on the daemon.

For more information, type man 1M gated at the HP-UX prompt.

The gated Routing Table

Sending gated a SIGINT signal causes gated to write information about interface con???gurations, task information, and routing tables to the

/var/tmp/gated_dump ???le.

The ripquery Tool

You can use the /usr/sbin/ripquery support tool to query gated for RIP routing information. ripquery sends two types of commands: a POLL command and a RIP request command. gated responds to a POLL command by listing all routes learned from RIP that are in its routing table. This does not include the interface routes for the local network or routes from other protocols that are announced through RIP. When gated receives a RIP request command on a interface, it announces routes via RIP on that interface. This includes routes from other protocols that are imported by gated on the node.

You can use ripquery with the -p option to query other non-gated RIP routers. With this option, ripquery initially sends POLL commands and then, if there is no response, sends RIP request commands. The default query (POLL commands) sent by ripquery may not be supported by all RIP routers. For more information, type man 1M ripquery at the HP-UX prompt.

The ospf_monitor Tool

You can use the /usr/sbin/ospf_monitor support tool to query OSPF routers for information on OSPF routing tables, interfaces, and neighbors, as well as data on AS external databases, link-state databases, error logs, and input/output statistics. Running the ospf_monitor command displays a prompt that allows you to enter interactive commands. For details on using this tool, type man 1M ospf_monitor at the HP-UX prompt.

Con???guring gated

Troubleshooting gated

Common Problems

This section discusses the common problems experienced during gated operation.

Problem 1: gated does not act as expected.

First, check the syslogd output for any syntax errors that may have been ???agged.

To detect incorrect con???guration commands, use gated tracing. Following are two sample con???gurations, along with the trace ???les generated by gated. The node used has three interfaces: lan0, lan1, and lan2. In the con???guration ???les, lan0, lan1, and lan3 are speci???ed. In the ???rst con???guration shown, the strictintfs option is speci???ed for the interfaces to ensure that gated exits when the error is detected.

Interface Con???guration With strictintfs Option Speci???ed The following con???guration references a non-existent interface. The options strictintfs line in the interfaces statement ensures that all the con???gured interfaces exit before gated starts.

traceoptions "tt" general; interfaces {

options strictintfs ;

interface lan0 lan1 lan3 passive ;

} ;

rip yes ;

The following is the tracing output that is produced when gated is started with this con???guration:

trace_on: Tracing to "/tt" started

Tracing flags enabled: general

parse: conf.tt:4 Interface not found at ???lan3???

parse_parse: 2 parse errors

Exit gated[15941] version @(#)Revision: 1.0 based on Cornell G ateD R3_5Beta_3

Con???guring gated

Troubleshooting gated

Interface Con???guration Without strictintfs Option Speci???ed The following con???guration references a non-existent interface, but does not include the strictintfs option:

traceoptions "tt" general; interfaces {

interface lan0 lan1 lan3 passive ;

} ;

rip yes ;

The following is the tracing output that is produced when gated is started with this con???guration:

trace_on: Tracing to "/tt" started

Tracing flags enabled: general

inet_routerid_notify: Router ID: 15.13.119.134

You can also ???nd the results of this same command in the gated_dump ???le. In the following segment of a gated_dump ???le, the interface is listed as passive in the interface policy statement toward the end of this example:

Interfaces:

Con???guring gated

Troubleshooting gated

Interface policy:

Interface lan0 lan1 lan3 passive

The state recorded in lan2 does not contain the NoAge ???ag, because the interface was not set to passive in the interface policy statement.

A common mistake is to expect gated to always send out RIP packets when you specify rip yes in a con???guration ???le. gated will be an active RIP participant only if the host is a router (that is, when the host has more than one network interface).

Problem 2: gated deletes routes from the routing table.

gated maintains a complete routing table in user space, and synchronizes this table with the kernel routing table. When gated starts, it reads the entries in the kernel routing table. However, if gated does not get con???rmation from its routing protocols (RIP, OSPF, and so on) about a route, it deletes the route from its tables and from the kernel routing table.

Con???guring gated

Troubleshooting gated

Normally, gated deletes the route con???gured in the /etc/rc.config.d/netconf ???le. To solve this problem, con???gure a static default route as described in the section ???Installing Static Routes??? on page 90.

Another common scenario occurs in networks where all the gateways do not implement the gated routing protocols. In this situation, routes that do not use gated gateways are not con???rmed by gated, and gated deletes them unless a static statement is included in /etc/gated.conf:

static {

13.0.0.0 mask 0xff000000 gateway 15.14.14.14 ;

};

The static entry in this example ensures that the local system includes a route to network 13.0.0.0 even though the gateway to that network (15.14.14.14) is not running any of the gated protocols.

You can include the restrict clauses in the export statements to restrict these extra routes from being advertised.

Problem 3: gated adds routes that appear to be incorrect.

If gated adds routes that appear to be incorrect, track the original source of the route by completing the following steps:

1.Start by looking at the routing table maintained by gated.

2.Send gated a SIGINT signal, and look at the information output in the /var/tmp/gated_dump ???le.

3.Look for the entry of the route in question. The entry identi???es the protocol over which this route was heard and the ???rst-hop router. The ???rst-hop router is likely to be the immediate source of the information.

Perform one of the following actions:

???If the route was learned over RIP, use /usr/sbin/ripquery to query the ???rst-hop router for the route. That router may claim to have heard the route from another router.

???If the ???rst-hop router is another host running gated, have that host???s gated dump its routing table to ???nd out where it learned about the route.

Con???guring gated

Troubleshooting gated

You may have to repeat this process several times to track down the original source of the route. If you expect the route to go through a different router, turn on gated tracing. The tracing tells you which routers are advertising this route and the values attached to those routes.

Problem 4: gated does not add routes that you think it must.

Tracking down this problem is similar to the previous problem (???Problem 3: gated adds routes that appear to be incorrect.??? on page 107). You expect one or more routers to advertise the route. Turn on gated tracing to verify that gated is receiving packets of the type of routing protocol you expect. If these packets do not contain a route you expect to be there, trace packets on the router you expect to advertise the route.

109

110

111

112

Index

TOS

routing feature, 24 traceoptions statement

in /etc/gated.conf ???le, 53 tracing

gated, 92, 99, 101

transmitdelay statement in /etc/gated.conf ???le, 68

TRPB, 18

Truncated Reverse Path Broadcasting, 18 See TRPB

trustedgateways clause

in /etc/gated.conf ???le, 53, 59

TTL

in mrouted, 33 tunnel command in mrouted, 32

tunnelling

in mrouted, 18 type of service

See TOS

type value

in /etc/gated.conf ???le, 82

U

/usr/tmp/mrouted.dump ???le, 38

V

/var/adm/syslog/syslog.log ???le, 36 /var/tmp/mrouted.cache ???le, 38 /var/tmp/mrouted.dump ???le, 38 version clause

in /etc/gated.conf ???le, 52 virtual interface table, 38 virtual links in OSPF, 77

113