IRIX® Admin: Networking and Mail Document Number 007-2860-006 CONTRIBUTORS Written by Arthur Evans and Jeffrey B. Zurschmeide. Updated by Pam Sogard, Helen Vanderberg, Bob Bernard,Terry Schultz, and Julie Boney Edited by Christina Cary, Cindy Kleinfeld, and Susan Wilkening Production by Amy Swenson and Glen Traefald Engineering contributions by Scott Henry, Carlin Otto, Kam Kashani, Chris Wagner, Paul Mielke, Robert Stephens, Joe Yetter, Gretchen Helms, John Schimmel, Robert Mende, Vernon Schryver, Michael Nelson, and Landon Noll Illustrations by Dany Galgani Cover design and illustration by Rob Aguilar, Rikk Carey, Dean Hodgkinson, Erik Lindholm, and Kay Maitz © Copyright 1996 - 2000 Silicon Graphics, Inc.— All Rights Reserved The contents of this document may not be copied or duplicated in any form, in whole or in part, without the prior written permission of Silicon Graphics, Inc. LIMITED AND RESTRICTED RIGHTS LEGEND Use, duplication, or disclosure by the Government is subject to restrictions as set forth in the Rights in Data clause at FAR 52.227-14 and/or in similar or successor clauses in the FAR, or in the DOD, DOE or NASA FAR Supplements. Unpublished rights reserved under the Copyright Laws of the United States. Contractor/manufacturer is SGI, 1600 Amphitheatre Pkwy., Mountain View, CA 94043-1351. Silicon Graphics, Challenge, IRIX,IRIS, and Onyx are registered trademarks and SGI, 4DDN, 4DLT, CHALLENGE, FDDI Visualyzer, IRIS InSight, IRIX NetWorker, IRIS 4D, NetVisualyzer, and the SGI logo are trademarks of Silicon Graphics, Inc. DSI is a trademark of Digicom Systems, Inc. FLEXlm is a trademark of GLOBEtrotter Software, Inc. Hayes is a registered trademark of Hayes Microcomputer Products, Inc. IBM 3270 is a trademark of International Business Machines, Inc. Intel is a registered trademark of Intel Corporation. Macintosh is a registered trademark of Apple Computer Corporation. MS-DOS is a registered trademark of Microsoft Corporation. Netscape is a trademark of Netscape Communications Corporation. Sun and RPC are registered trademarks and NFS is a trademark of Sun Microsystems, Inc. Tektronix is a trademark of Tektronix, Inc. Telebit is a registered trademark of Telebit Corporation. Robotics is a registered trademark of U. S. Robotics, Inc. X Window System is a trademark of X Consortium, Inc. ZyXEL is a trademark of ZyXEL. IRIX® Admin: Networking and Mail Document Number 007-2860-006 What’s New in This Guide This rewrite of the IRIX Admin: Networking and Mail guide supports the 6.5.7 release of the IRIX operating system. Major Documentation Changes The IRIX sendmail mail system has been updated to reflect the standard sendmail facility. The sendmail.cf file is now created from the sendmail.mc file. The sendmail.cf file is read in real time by each copy of sendmail, thus eliminating the need for the sendmail.fc file. It is no longer necessary to manipulate the sendmail.cf file. Instead, you can enable various features by editing the set of definitions, configurations, and commands found in the sendmail.cf file and then using the following command: configmail mc2cf Chapter 9, “IRIX sendmail,” and Appendix B, “IRIX sendmail Reference,” describe the macro definitions and configuration options for implementing the sendmail facility. iii Record of Revision Version Description 006 February 2000 Incorporates information for the IRIX 6.5.7 release v Contents List of Figures xvii List of Tables xix IRIX Admin Manual Set xxi About This Guide xxiii What This Guide Contains xxiii Conventions Used in This Guide xxiv Additional Resources xxv Reader Comments xxvii 1. About Networking Products 1 Networking Hardware 1 Basic Network Attachment 2 Networking Hardware Options 3 Controller Interface Names 4 Networking Software 4 Optional Networking Products 5 2. Planning a Network 7 Planning the Physical Network 7 About Repeaters, Bridges, Routers, and Gateways 8 About Network Performance 9 About Wide Area Networks 10 Internet Protocol Addresses 14 Format of Internet Protocol (IP) Version 4 Addresses 15 Obtaining a Network Number 17 Required Information for Obtaining an Internet Address 18 vii Contents Domain Names 18 Obtaining a Domain Name 19 About Subdomains 19 About Internet Connections 20 Before Connecting to the Internet 20 About Local Network Information Centers 21 Online Information Sources 23 About Name-to-Address Mapping 26 /etc/hosts Database 26 Domain Name System 27 Network Information Service (NIS) 27 Guidelines for a Subnetwork 28 IP Address Allocation 30 About Network Security 31 Common Network Applications 31 About Electronic Mail 31 About Network File System (NFS) 31 3. Setting Up a Network 33 Configuring a System for a Network 33 Attaching Your Station to an Ethernet Network 34 Checking Your Ethernet Connection 34 Checking the Network Software Configuration 36 About the Hosts Database 37 Modifying the Hosts Database 38 Naming Your Station 39 Testing Your Network Connectivity 40 viii Contents Setting Up a Router 40 Configuring a Router With Two Interfaces 41 Configuring a Router With More Than Two Interfaces 42 Configuring Routing Behavior 43 Turning On Multicast Routing 44 About Multicast Packets Forwarding 44 Setting Up Tunnels to Support Multicast Packets 46 Updating /etc/rpc for NIS Users 47 Subnetting a Network 48 Setting the Netmask 48 Rebooting the Station 49 Modifying the Network Interface Configuration With the /etc/config/netif.options File 49 Modifying the Interface Name in the /etc/config/netif.options File 50 Modifying the Interface Address in the /etc/config/netif.options File 51 Assigning IP Aliases 52 Changing Network Parameters in the ifconfig-#.options File 55 Configuring /etc/gateways Files for Networks That Do Not Support Broadcast or Multicast 57 /etc/gateways File Format 57 Examples of /etc/gateways Files 59 Configuring Multiple Network Interfaces 60 Dynamic Host Configuration With Proclaim 61 Configuring the DHCP Server 62 Configuring the DHCP Relay Agent 63 About the Proclaim Client 63 Limitations of DHCP 64 Creating a Local Network Script 64 Turning On Remote Access Logging 64 Setting Up Network-Wide Services 65 Setting Up an Anonymous FTP Account 65 Setting Up a Password-Protected FTP Account 69 About IRIS InSight File Servers 71 ix Contents Accessing Network Services through Internet Gateway 75 Reserving Resources With RSVP 76 Installing RSVP 76 Troubleshooting RSVP 78 Troubleshooting Your Ethernet Connection 79 Troubleshooting Cable Problems 79 Troubleshooting Late-Collision Problems 80 Troubleshooting Packet Size Problems 80 Troubleshooting Server Contact Problems 81 Checking Additional Network Interfaces 82 4. Introducing Network Management 85 Resources for Network Management 85 About Network Management Functions 86 About Network Startup and Shutdown 87 Network Initialization Process 87 Network Shutdown Process 89 Network Management Tools 89 Interpreting Network Statistics 93 Testing Network Connectivity With ping 93 Measuring Network Throughput With ttcp 94 Collecting Network Statistics With netstat 96 Network Tuning Information 97 About Setting MTU Sizes 98 About Setting Packet Forwarding 98 About Setting Window Sizes 98 HTTP Considerations 99 Troubleshooting Poor Network Performance 99 Troubleshooting Hardware Problems to Improve Network Performance 99 Troubleshooting Network Configuration to Improve Network Performance 100 Troubleshooting Network Daemons to Improve Network Performance 101 Decreasing Packet Size to Improve Network Performance 101 Kernel Configuration for Better Network Performance 102 x Contents 5. SLIP and PPP 103 About SLIP and PPP 104 Setting Up a SLIP or PPP Connection: General Procedures 105 Verifying the SLIP and PPP Software 106 Installing the SLIP and PPP Software 107 Selecting a Modem 107 IP Addresses for SLIP and PPP Clients 107 Configuring a System for Dial-Out 108 Configuration Files for Dial-Out 108 Sample SLIP Configuration for Dial-Out 112 Sample PPP Configuration for Dial-Out 112 Configuring a System for Dial-In 114 Configuring /etc/passwd for Dial-In With SLIP 114 Configuring /usr/etc/remoteslip for Dial-In With SLIP 114 Configuring /etc/passwd for Dial-In With PPP 115 SLIP and PPP Routing and Address Allocation 116 About Proxy-ARP Routing for SLIP Connections 117 Setting Up SLIP/PPP Subnets for Client Addresses 119 About Connected SLIP or PPP Networks 119 Using Dynamic Address Allocation With PPP 119 Configuring a Bidirectional Link 120 Starting SLIP or PPP at Boot Time 120 About Demand Dialing 121 Setting Up Demand Dialing 121 NFS Over SLIP or PPP 121 File Transfer Over SLIP or PPP 122 Troubleshooting SLIP and PPP Links 122 6. BIND Name Server 125 About Domain Name Service 126 xi Contents BIND Servers and Clients 128 BIND Master Servers 129 BIND Slave and Forwarding Servers 129 BIND Caching-Only Server 130 BIND Clients 130 BIND Configuration Files 130 BIND Boot File 132 BIND named.hosts File 134 BIND named.rev File 135 BIND localhost.rev File 135 BIND root.cache File 135 BIND /etc/config/named.options File 135 hoResolution With /etc/resolv.conf 136 Setting Up a BIND Configuration 137 Configuring the Primary BIND Server 138 Configuring the Secondary BIND Server 142 Configuring a Caching-Only BIND Server 143 Configuring the Forwarding BIND Server 144 Configuring a Slave BIND Server 145 Configuring the BIND Client 146 Managing the BIND Environment 146 Adding a New BIND Station 147 Deleting a BIND Station 147 Adding Another BIND Domain 147 named Reload Script 147 named Restart Script 148 Debugging named 148 SYSLOG Error Messages 149 Debugging Name Servers With the nslookup Command 150 7. Unified Name Service 151 About Unified Name Service 152 xii Contents Overview of UNS Operations 152 How UNS Works With NIS 155 About UNS and the NIS Database 158 How UNS Works With BIND 158 How UNS Works With NFS 159 How UNS Works With LDAP 160 Namespace Format 161 UNS Configuration File 162 Setting Up a UNS Configuration 163 UNS Protocol Libraries 163 UNS File Structure Attributes 167 Setting Domain Attributes 167 Setting Table Attributes 168 Setting Library Attributes 168 Setting File Attributes 168 Querying Attributes 168 Cache Tuning 169 Troubleshooting nsd 169 General Approach to Troubleshooting 169 Deciphering nsd Signals 170 Verifying /ns/.local 170 8.