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TCP/IP and Data Communications Administration Guide

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TCP/IP and Data Communications Administration Guide TCP/IP and Data Communications Administration Guide Sun Microsystems, Inc. 901 San Antonio Road Palo Alto, CA 94043-1100 U.S.A. Part No: 805–4003–10 October 1998 Copyright 1998 Sun Microsystems, Inc. 901 San Antonio Road, Palo Alto, California 94303-4900 U.S.A. All rights reserved. This product or document is protected by copyright and distributed under licenses restricting its use, copying, distribution, and decompilation. No part of this product or document may be reproduced in any form by any means without prior written authorization of Sun and its licensors, if any. Third-party software, including font technology, is copyrighted and licensed from Sun suppliers. Parts of the product may be derived from Berkeley BSD systems, licensed from the University of California. UNIX is a registered trademark in the U.S. and other countries, exclusively licensed through X/Open Company, Ltd. Sun, Sun Microsystems, the Sun logo, SunDocs, Java, the Java Coffee Cup logo, and Solaris are trademarks, registered trademarks, or service marks of Sun Microsystems, Inc. in the U.S. and other countries. All SPARC trademarks are used under license and are trademarks or registered trademarks of SPARC International, Inc. in the U.S. and other countries. Products bearing SPARC trademarks are based upon an architecture developed by Sun Microsystems, Inc. The OPEN LOOK and SunTM Graphical User Interface was developed by Sun Microsystems, Inc. for its users and licensees. Sun acknowledges the pioneering efforts of Xerox in researching and developing the concept of visual or graphical user interfaces for the computer industry. Sun holds a non-exclusive license from Xerox to the Xerox Graphical User Interface, which license also covers Sun’s licensees who implement OPEN LOOK GUIs and otherwise comply with Sun’s written license agreements. RESTRICTED RIGHTS: Use, duplication, or disclosure by the U.S. Government is subject to restrictions of FAR 52.227–14(g)(2)(6/87) and FAR 52.227–19(6/87), or DFAR 252.227–7015(b)(6/95) and DFAR 227.7202–3(a). DOCUMENTATION IS PROVIDED “AS IS” AND ALL EXPRESS OR IMPLIED CONDITIONS, REPRESENTATIONS AND WARRANTIES, INCLUDING ANY IMPLIED WARRANTY OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT, ARE DISCLAIMED, EXCEPT TO THE EXTENT THAT SUCH DISCLAIMERS ARE HELD TO BE LEGALLY INVALID. Copyright 1998 Sun Microsystems, Inc. 901 San Antonio Road, Palo Alto, Californie 94303-4900 Etats-Unis. Tous droits réservés. Ce produit ou document est protégé par un copyright et distribué avec des licences qui en restreignent l’utilisation, la copie, la distribution, et la décompilation. Aucune partie de ce produit ou document ne peut être reproduite sous aucune forme, par quelque moyen que ce soit, sans l’autorisation préalable et écrite de Sun et de ses bailleurs de licence, s’il y en a. Le logiciel détenu par des tiers, et qui comprend la technologie relative aux polices de caractères, est protégé par un copyright et licencié par des fournisseurs de Sun. Des parties de ce produit pourront être dérivées du système Berkeley BSD licenciés par l’Université de Californie. UNIX est une marque déposée aux Etats-Unis et dans d’autres pays et licenciée exclusivement par X/Open Company, Ltd. Sun, Sun Microsystems, le logo Sun, SunDocs, Java, le logo Java Coffee Cup, et Solaris sont des marques de fabrique ou des marques déposées, ou marques de service, de Sun Microsystems, Inc. aux Etats-Unis et dans d’autres pays. Toutes les marques SPARC sont utilisées sous licence et sont des marques de fabrique ou des marques déposées de SPARC International, Inc. aux Etats-Unis et dans d’autres pays. Les produits portant les marques SPARC sont basés sur une architecture développée par Sun Microsystems, Inc. L’interface d’utilisation graphique OPEN LOOK et SunTM a été développée par Sun Microsystems, Inc. pour ses utilisateurs et licenciés. Sun reconnaît les efforts de pionniers de Xerox pour la recherche et le développement du concept des interfaces d’utilisation visuelle ou graphique pour l’industrie de l’informatique. Sun détient une licence non exclusive de Xerox sur l’interface d’utilisation graphique Xerox, cette licence couvrant également les licenciés de Sun qui mettent en place l’interface d’utilisation graphique OPEN LOOK et qui en outre se conforment aux licences écrites de Sun. CETTE PUBLICATION EST FOURNIE “EN L’ETAT” ET AUCUNE GARANTIE, EXPRESSE OU IMPLICITE, N’EST ACCORDEE, Y COMPRIS DES GARANTIES CONCERNANT LA VALEUR MARCHANDE, L’APTITUDE DE LA PUBLICATION A REPONDRE A UNE UTILISATION PARTICULIERE, OU LE FAIT QU’ELLE NE SOIT PAS CONTREFAISANTE DE PRODUIT DE TIERS. CE DENI DE GARANTIE NE S’APPLIQUERAIT PAS, DANS LA MESURE OU IL SERAIT TENU JURIDIQUEMENT NUL ET NON AVENU. Please Recycle Contents Preface xvii Part I Setting Up and Administering TCP/IP Networks 1. Overview of Network Administration 3 Responsibilities of the Network Administrator 3 Designing the Network 4 Setting Up the Network 4 Maintaining the Network 4 Expanding the Network 5 What is TCP/IP? 5 Types of Hardware That Make Up a Solaris Network 6 How Network Software Transfers Information 7 Reaching Beyond the Local-Area Network—the Wide-Area Network 10 TCP Large Window Support 10 TCP Selective Acknowledgment Support 14 2. TCP/IP Protocol Suite 15 Introducing the Internet Protocol Suite 15 Protocol Layers and the OSI Model 16 TCP/IP Protocol Architecture Model 17 How the TCP/IP Protocols Handle Data Communications 22 Contents iii Data Encapsulation and the TCP/IP Protocol Stack 23 Finding Out More About TCP/IP and the Internet 26 Computer Trade Books 26 RFCs and FYIs 26 3. Planning Your Network 29 Designing the Network 29 Factors Involved in Network Planning 30 Setting Up an IP Addressing Scheme 30 Parts of the IP Address 31 Network Classes 32 How IP Addresses Apply to Network Interfaces 35 Naming Entities on Your Network 35 Administering Host Names 36 Selecting a Name Service 36 Registering Your Network 38 InterNIC and InterNIC Registration Services 38 How to Contact the InterNIC 39 Adding Routers 39 Network Topology 39 How Routers Transfer Packets 41 4. Configuring TCP/IP on the Network 43 Before You Configure TCP/IP 44 Determining Host Configuration Modes 44 Machines That Should Run in Local Files Mode 45 Machines That Are Network Clients 46 Mixed Configurations 46 Sample Network 46 TCP/IP Configuration Files 47 iv TCP/IP and Data Communications Administration Guide ♦ October 1998 /etc/hostname.interface File 48 /etc/nodename File 49 /etc/defaultdomain File 49 /etc/defaultrouter File 49 hosts Database 49 netmasks Database 52 r How to Add a Subnet to a Network 55 Network Databases and nsswitch.conf File 56 How Name Services Affect Network Databases 56 nsswitch.conf File — Specifying Which Name Service to Use 58 bootparams Database 60 ethers Database 61 Other Network Databases 62 protocols Database 63 services Database 63 Network Configuration Procedures 64 r How to Configure a Host for Local Files Mode 65 r Setting Up a Network Configuration Server 66 r How to Set Up a Network Configuration Server 66 Configuring Network Clients 67 r How to Configure Hosts for Network Client Mode 67 r How to Specify a Router for the Network Client 68 Configuring Standard TCP/IP Services 69 Overview of the Booting Processes 70 5. Configuring Routers 71 Routing Protocols 71 Routing Information Protocol (RIP) 71 ICMP Router Discovery (RDISC) Protocol 72 Contents v Configuring Routers 72 Configuring Both Router Network Interfaces 72 r How to Configure a Machine as a Router 73 How a Machine Determinesif it is a Router 73 Automatic Routing Protocol Selection 74 Forcing a Machine to Be a Router 74 Creating a Multihomed Host 75 r How to Create a Multihomed Host 75 Turning On Space-Saving Mode 76 Turning Off ICMP Router Discovery on the Host 76 Turning Off ICMP Router Discovery on the Router 76 6. Troubleshooting TCP/IP 77 General Troubleshooting Methods 77 Running Software Checks 78 ping Command 78 ifconfig Command 80 netstat Command 81 Displaying Per Protocol Statistics 81 Displaying Network Interface Status 83 Displaying Routing Table Status 83 Logging Network Problems 84 Displaying Packet Contents 84 r How to check all packets from your system 85 r How to capture snoop results to a file 86 r How to check packets between server and client 86 Displaying Routing Information 87 How to Run the Traceroute Utility 87 Part II Expanding Your Network With PPP vi TCP/IP and Data Communications Administration Guide ♦ October 1998 7. Understanding PPP 91 Overview of Solaris PPP 91 Solaris PPP Specifications 91 Transmission Facilities Used by PPP 92 Standards Conformance 92 PPP Network Interfaces 93 Extending Your Network With PPP 93 Point-to-Point Communications Links 93 Point-to-Point Configurations Supported by Solaris PPP 94 Multipoint Communications Links 97 Multipoint Configurations Supported by PPP 97 Introducing the PPP Software 99 Link Manager 99 Login Service 100 Configuration File 100 Log File 101 FIFO File 101 UUCP Databases 101 How the Components Work Together 101 Outbound Connections Scenario 101 Inbound Connections Scenario 102 PPP Security 103 8. Preparing Your PPP Configuration 105 Determining Requirements for Your Configuration Type 106 Remote Computer-to-Network Configuration 106 Remote Host-to-Remote Host Configuration 107 Network-to-Network Configuration 108 Dial-in Server With Dynamic Point-to-Point Links 108 Contents vii Multipoint Dial-in Server 109 Hosts on a Virtual Network 110 Determining IP Addressing for Your PPP Link 110 Specifying IP Addresses 111 Types of Addressing Schemes 111 Routing
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