Network Administration for the Solaris 9 Operating Environment SA-399 Student Guide phần 1 doc

Enterprise Services, Revision APreface About This Course Instructional Goals Upon completion of this course, you should be able to: ● Configure the Network Interface layer ● Configure th

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Table of Contents

About This Course xv

Instructional Goals xv

Course Map xvi

Topics Not Covered xvii

How Prepared Are You? xviii

Introductions xix

How to Use Course Materials xx

Conventions xxi

Icons xxi

Typographical Conventions xxi

Introducing the TCP/IP Model 1-1

Objectives 1-1 Introducing Network Model Fundamentals 1-2 Network Protocols 1-2 Network Model Concepts 1-3 Introducing the Layers of the TCP/IP Model 1-4 Network Interface Layer 1-5 Internet Layer 1-6 Transport Layer 1-7 Application Layer 1-8 Describing Basic Peer-to-Peer Communication and Related

Protocols 1-10 Peer-to-Peer Communication 1-10 TCP/IP Protocols 1-11 Exercise: Reviewing the TCP/IP Model 1-15 Tasks 1-15 Exercise Summary 1-17 Exercise Solutions 1-18

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vi Network Administration for the Solaris™ 9 Operating Environment

Introducing LANs and Their Components 2-1

Objectives 2-1Introducing Network Topologies 2-2Bus Topologies 2-2Star Topologies 2-3Ring Topologies 2-4VLAN Topologies 2-5Introducing LAN Media 2-9IEEE Identifiers 2-9IEEE 802.3 Type 2-10Introducing Network Devices 2-14Shared Hubs 2-14Bridges 2-14Switches 2-14Exercise: Reviewing LANs and Their Components 2-16Preparation 2-16Tasks 2-16Exercise Summary 2-18Exercise Solutions 2-19

Describing Ethernet Interfaces 3-1

Objectives 3-1Introducing Ethernet Concepts 3-2Major Ethernet Elements 3-2CSMA/CD Access Method 3-2Full-Duplex and Half-Duplex Transmission 3-4Ethernet Statistics 3-4Introducing Ethernet Frames 3-6Ethernet Addresses 3-6Setting a Local Ethernet Address 3-8Ethernet-II Frame Analysis 3-10Ethernet Frame Encapsulation 3-11Maximum Transfer Units 3-13Ethernet Frame Errors 3-14Using Network Utilities 3-15Using thesnoop Utility 3-15Using thenetstat Utility 3-18Using thendd Utility 3-19Exercise: Reviewing Ethernet Interfaces 3-22Preparation 3-22Tasks 3-22Exercise Summary 3-26Exercise Solutions 3-27

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Describing ARP and RARP 4-1

Objectives 4-1Introducing ARP 4-2Purpose of ARP 4-2Operation of ARP 4-3Introducing RARP 4-7Purpose of RARP 4-7Operation of RARP 4-7Exercise: Reviewing ARPs and RARPs 4-10Preparation 4-10Tasks 4-11Exercise Summary 4-14Exercise Solutions 4-15

Configuring IP 5-1

Objectives 5-1Introducing the Internet Layer Protocols 5-2Purpose of IP 5-2Purpose of ICMP 5-3Introducing the IP Datagram 5-5

IP Datagram Header Fields 5-5

IP Datagram Payload 5-6Introducing IP Address Types 5-7Unicast Addresses 5-7Broadcast Addresses 5-8Multicast Addresses 5-9Introducing Subnetting and VLSM 5-10Subnetting 5-10The/etc/inet/netmasks File 5-11VLSM 5-12Introducing the Interface Configuration Files 5-14The/etc/hostname.interface File 5-14The/etc/inet/hosts File 5-14The/etc/nodename File 5-15Administering Logical Interfaces 5-16Introducing Logical Interfaces 5-16Configuring Logical Interfaces 5-17Unconfiguring Logical Interfaces 5-20Exercise: Reviewing IP 5-21Preparation 5-21Task Summary 5-21Tasks 5-22Exercise Summary 5-24Exercise Solutions 5-25

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viii Network Administration for the Solaris™ 9 Operating Environment

Configuring Multipathing 6-1

Objectives 6-1Increasing Network Throughput and Availability 6-2Limitations of Network Interfaces 6-2Implementing Multipathing 6-4Introducing Multipathing 6-4Configuring Multipathing Using Configuration Files 6-7Configuring Multipathing Using the

Command Line 6-12Viewing Multipath Operation 6-20Troubleshooting a Multipath

Network Configuration 6-22Exercise: Reviewing Multipathing 6-24Preparation 6-24Tasks 6-26Exercise Summary 6-30Exercise Solutions 6-31

Configuring Routing 7-1

Objectives 7-1Identifying the Fundamentals of Routing 7-2Purpose of Routing 7-2Routing Types 7-3Introducing Route Table Population 7-4Static Route 7-4Dynamic Route 7-4Introducing Routing Protocol Types 7-6Autonomous Systems 7-6Interior Routing Protocols 7-7Exterior Routing Protocols 7-8Introducing the Route Table 7-9Displaying the Route Table 7-9Introducing Route Table Entries 7-10Introducing Route Table Search Order 7-12Associating Network Name and Network Number 7-14Configuring Static Routes 7-16Configuring Static Direct Routes 7-16Configuring the/etc/defaultrouter File 7-16Configuring the/etc/gateways File 7-17Configuring Manual Static Routes 7-18Using the RDISC Protocol 7-21Configuring Dynamic Routing 7-23RIP Version 1 7-23Thein.routed Process 7-25ICMP (Routing) Redirect 7-26

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Introducing CIDR 7-28Purpose of CIDR 7-28Operation of CIDR 7-28Configuring Routing at Boot Time 7-32Initializing the Router 7-32Configuring the Router Without Rebooting 7-34Initializing a Multihomed Host 7-34Initializing a Non-Router 7-36Troubleshooting Routing 7-37Troubleshooting the Router Configuration 7-37Troubleshooting Network Names 7-39Exercise: Reviewing Routing Configuration 7-40Preparation 7-40Tasks 7-42Exercise Summary 7-53Exercise Solutions 7-54

Configuring IPv6 8-1

Objectives 8-1Introducing IPv6 8-2The Need for IPv6 8-2Features of IPv6 8-3Introducing IPv6 Addressing 8-4Address Types 8-4IPv6 Address Representation 8-5Format Prefixes 8-5Introducing IPv6 Autoconfiguration 8-7Stateful Autoconfiguration 8-7Stateless Autoconfiguration 8-7Interface Identifier Calculation 8-8Duplicate Address Detection 8-9Introducing Unicast Address Types 8-10Link-Local Address Types 8-10Site-Local Address Types 8-10Aggregatable Global Unicast Address Types 8-11Prefix Notation 8-11Embedded IPv4 Addresses 8-12Unspecified Address Types 8-12Loopback Address Types 8-12Introducing Multicast Address Types 8-13Purpose of Multicast Addresses 8-13Scope Bits 8-14ICMPv6 Group Membership 8-15Enabling IPv6 8-16Thein.ndpd Process on the Non-Router 8-16IPv6 on Non-Routers Configuration 8-17

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x Network Administration for the Solaris™ 9 Operating Environment

Non-Router Configuration Troubleshooting 8-20Thein.ndpd Process on the Router 8-21IPv6 Routing Information Protocol 8-21IPv6 Router Configuration 8-22Router Configuration Troubleshooting 8-26Managing IPv6 8-28Displaying the State of IPv6 Interfaces 8-28Modifying an IPv6 Interface Configuration 8-28Configuring Logical Interfaces 8-29Troubleshooting IPv6 Interfaces 8-29Displaying the IPv6 Route Table 8-29Exercise: Configuring IPv6 8-30Preparation 8-30Tasks 8-30Exercise Summary 8-36Exercise Solutions 8-37Configuring IPv6 Multipathing 8-47Configuring IPMP Manually 8-47Configuring IPMP at Boot Time 8-57Exercise: Configuring IPv6 Multipathing 8-61Preparation 8-61Tasks 8-61Exercise Summary 8-64Exercise Solutions 8-65Configuring IPv6-Over-IPv4 Tunnels 8-70Introducing Tunnels 8-70Configuring Tunnels 8-70Routing Between Tunnels 8-77Troubleshooting IPv4 Tunnels 8-77Exercise: Configuring an IPv6-Over-IPv4 Tunnel 8-79Preparation 8-79Tasks 8-79Exercise Summary 8-81Exercise Solutions 8-82

Describing the Transport Layer 9-1

Objectives 9-1Introducing Transport Layer Fundamentals 9-2Protocol Characteristics 9-2Transport Protocols in TCP/IP 9-8Introducing UDP 9-9Purpose of UDP 9-9UDP Datagram Header 9-9Introducing TCP 9-10TCP Segment Header 9-10Virtual Circuit Connection 9-11

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Full-Duplex Connection 9-11Unstructured Stream Orientation 9-11Buffered Transfer 9-11Introducing TCP Flow Control 9-12Receiver-Side Window Advertisements 9-12Sender-Side Congestion Window 9-12TCP Large Window 9-13Exercise: Describing the Transport Layer 9-14Preparation 9-14Tasks 9-14Exercise Summary 9-15Exercise Solutions 9-16

Configuring DNS 10-1

Objectives 10-1Introducing DNS Basics 10-2BIND 10-2Top-Level Domains 10-2Zones of Authority 10-4Server Types 10-4Answer Types 10-7Name-Resolution Process 10-7Resource Records 10-10Configuring the DNS Server 10-14Gathering Information 10-14Editing the BIND Configuration File 10-14Editing thenamed.root File 10-17Editing the Forward-Domain File 10-19Editing the Reverse-Domain File 10-21Editing the Reverse-Loopback Domain File 10-22Configuring Dynamic Updates 10-23Configuring Security 10-23Configuring Secondary DNS Servers 10-25Configuring DNS Clients 10-26Troubleshooting the DNS Server Using Basic Utilities 10-28Examining the/var/adm/messages File 10-28Using thenslookup Utility 10-29Dumping a Snapshot of the DNS Database 10-31Changing the Debug Level of the Name Daemon 10-31Forcing thein.named Process to Reread Configuration Files 10-32

Modifying the DNS Server With thendc Utility 10-32Exercise: Configuring DNS 10-34Preparation 10-34Task Summary 10-34Tasks 10-35Exercise Summary 10-41Exercise Solutions 10-42

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xii Network Administration for the Solaris™ 9 Operating Environment

Configuring DHCP 11-1

Objectives 11-1Introducing the Fundamentals of DHCP 11-2Purpose of DHCP 11-2DHCP Client Functions 11-3DHCP Server Functions 11-4Configuring a DHCP Server 11-6Configuring DHCP Using Different Methods 11-7Using thedhcpconfig Utility 11-7Introducing thedhcp_network File 11-9Using thepntadm Utility 11-10Introducing thedhcptab Table 11-13Performing Initial DHCP Server Configuration by

Using thedhcpmgr Utility 11-17Adding Addresses by Using thedhcpmgr Utility 11-29Configuring and Managing DHCP Clients 11-37Configuring the DHCP Client 11-37Exercise: Configuring a DHCP Server and Client 11-39Preparation 11-39Task Summary 11-39Tasks 11-39Exercise Summary 11-42Exercise Solutions 11-43Task 1 – Configuring the DHCP Server 11-43Task 2 – Configuring the DHCP Client 11-61Task 3 – Using thesnoop Utility to View DHCP

Client-Server Interaction 11-62Configuring for Dynamic DNS 11-64Viewing Debug Output From the DNS Server 11-67Troubleshooting the DHCP Server 11-68Troubleshooting DHCP Clients 11-72Troubleshooting DHCP Client Host

Name Acquisition 11-72Configuring the DHCP Server to Support

JumpStart Clients 11-80Comparing Conventional JumpStart Procedure

With DHCP JumpStart Procedure Clients 11-80Performing a Configuration 11-80Configuring a DHCP Server to Allow a Client to

Boot From a JumpStart Server 11-86Configuring the JumpStart Server to Support

JumpStart in DHCP 11-106Testing the Client’s Ability to Jump Start by

Using DHCP 11-107

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Exercise: Configuring a DHCP Server and Client 11-109Preparation 11-109Task Summary 11-109Tasks 11-110Exercise Summary 11-112Exercise Solutions 11-113Task 1 – Configuring DNS to Support Dynamic

DNS Updates 11-113Task 2 – Configuring the DHCP Server to Perform

Dynamic DNS Updates 11-113Task 3 – Configuring the DHCP Server to Allow a

Client to Boot from a JumpStart Server 11-116

Configuring NTP 12-1

Objectives 12-1Identifying NTP Basics 12-2How Computers Keep Time 12-2Uses of NTP 12-3NTP Terms 12-3Configuring an NTP Server 12-5Using an Undisciplined Local Clock 12-7Using External NTP Reference Servers 12-9Managing Daemons 12-10Determining NTP Peers 12-11Configuring an NTP Client 12-12Establishing Basic Configuration 12-12Managing NTP Client Daemons 12-13Troubleshooting NTP 12-14Viewing Messages 12-14Using thesnoop Utility 12-15Exercise: Configuring NTP 12-16Preparation 12-16Task Summary 12-16Tasks 12-16Exercise Summary 12-19Exercise Solutions 12-20

Bibliography Bibliography-1

Sun Microsystems Publications Bibliography-1Books Bibliography-1Online References Bibliography-2Requests for Comments (RFCs) Bibliography-3

Glossary/Acronyms Glossary-1 Index Index-1

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Preface

About This Course

Instructional Goals

Upon completion of this course, you should be able to:

● Configure the Network Interface layer

● Configure the network (Internet and Transport layers)

● Configure and manage network applications

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Course Map

Preface-xvi Network Administration for the Solaris™ 9 Operating Environment

Course Map

The course map enables you to see what you have accomplished andwhere you are going in reference to the instructional goals

Configuring DNS ConfiguringDHCP ConfiguringNTP

Configuring Routing ConfiguringIPv6

Describing the Transport Layer

Introducing the TCP/IP Model

Introducing LANs and Their Components

Describing Ethernet Interfaces

Describing ARP and RARPConfiguring the Network Interface Layer

Configuring the Network

Configuring

IP MultipathingConfiguring

Configuring and Managing Network Applications

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Topics Not Covered

This course does not cover the following topics Many of these topics arecovered in other courses offered by Sun Educational Services:

● Solaris™ Operating Environment (Solaris OE) system

administration – Covered in SA-239: Intermediate System

Administration for the Solaris™ 9 Operating Environment and

SA-299: Advanced System Administration for the Solaris™ 9 Operating

Environment

● Server storage administration – Covered in ES-220: Disk Management

with DiskSuite™ and ES-310: Volume Manager With Sun StorEdge™

● NIS+ – Covered in SA-385: NIS+ Administration

● Solaris OE tuning – Covered in SA-400: Solaris™ Systems Performance

Management

Refer to the Sun Educational Services catalog for specific information andregistration

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How Prepared Are You?

Preface-xviii Network Administration for the Solaris™ 9 Operating Environment

How Prepared Are You?

To be sure you are prepared to take this course, can you answer yes to thefollowing questions?

● Can you perform basic host operations, such as startup andshutdown, to initialize certain network configuration changes?

● Can you manipulate startup and shutdown scripts to configurenetworks?

● Can you set up user accounts when configuring network services forsystem users?

● Can you locate and install network software packages required to set

up various network services?

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● Title, function, and job responsibility

● Experience related to topics presented in this course

● Reasons for enrolling in this course

● Expectations for this course

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How to Use Course Materials

Preface-xx Network Administration for the Solaris™ 9 Operating Environment

How to Use Course Materials

To enable you to succeed in this course, these course materials employ alearning module that is composed of the following components:

● Objectives – You should be able to accomplish the objectives aftercompleting a portion of instructional content Objectives supportgoals and can support other higher-level objectives

● Lecture – The instructor will present information specific to theobjective of the module This information will help you learn theknowledge and skills necessary to succeed with the activities

● Activities – The activities take on various forms, such as an exercise,self-check, discussion, and demonstration Activities are used tofacilitate mastery of an objective

● Visual aids – The instructor might use several visual aids to convey aconcept, such as a process, in a visual form Visual aids commonlycontain graphics, animation, and video

Note – Many system administration tasks for the Solaris OE can be

accomplished in more than one way The methods presented in thecourseware reflect recommended practices used by Sun EducationalServices

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Discussion – Indicates a small-group or class discussion on the current

topic is recommended at this time

Note – Indicates additional information that can help students but is not

crucial to their understanding of the concept being described Studentsshould be able to understand the concept or complete the task withoutthis information Examples of notational information include keywordshortcuts and minor system adjustments

Caution – Indicates that there is a risk of personal injury from a

nonelectrical hazard, or risk of irreversible damage to data, software, orthe operating system A caution indicates that the possibility of a hazard(as opposed to certainty) might happen, depending on the action of theuser

Typographical Conventions

Courieris used for the names of commands, files, directories, usernames, host names, programming code, and on-screen computer output;for example:

Use thels -alcommand to list all files

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Preface-xxii Network Administration for the Solaris™ 9 Operating Environment

Courier italicsis used for variables and command-line placeholdersthat are replaced with a real name or value; for example:

To delete a file, use thermfilenamecommand

Courier italic boldis used to represent variables whose values are to

be entered by the student as part of an activity; for example:

Type chmod a+rwx filenameto grant read, write, and executerights for filename

Palatino italics is used for book titles, new words or terms, or words that

you want to emphasize; for example:

Read Chapter 6 in the User’s Guide.

These are called class options.

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Upon completion of this module, you should be able to:

● Describe network model fundamentals

● Describe the layers of the TCP/IP model

● Describe basic peer-to-peer communication and related protocols

The following course map shows how this module fits into the currentinstructional goal

Figure 1-1 Course Map

Introducing the TCP/IP Model

Introducing LANs and Their Components

Describing Ethernet Interfaces

Describing ARP and RARPConfiguring the Network Interface Layer

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Introducing Network Model Fundamentals

1-2 Network Administration for the Solaris™ 9 Operating Environment

The fundamentals required to understand computer networking are thenetwork model, the functions of the layers, and the protocols that governdata transfer between two or more systems

Network Protocols

Computer networks use protocols to communicate Protocols define theprocedures to be followed by the systems involved in the communicationprocess A data communication protocol is a set of rules that must befollowed for two electronic devices to communicate with each other.These rules describe:

● Syntax – Data format and coding

● Semantics – Control information and error handling

● Timing – Speed matching and sequencing

Functions of Protocols

A protocol defines how systems can communicate and facilitatescommunication between software, firmware, and other devices in datatransfer

Each protocol provides a function essential for data communication Eachsoftware module that implements a protocol can be developed andupdated independently of other modules, as long as the interface betweenthe modules remains constant

Many protocols provide and support data communication Manyprotocols are used so that communication can be broken into smaller,manageable processes They form a communication architecture, alsoknown as a protocol stack The TCP/IP model is a protocol stack used bythe Solaris™ Operating Environment (Solaris OE) for data

communication

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The features of a protocol stack are:

● Each layer has a specific purpose and exists on both the sourceand destination hosts

● Each layer communicates with a peer layer on another host in agiven process of communication

● Each layer on a host acts independently of other layers on thesame machine but is synchronous with the same layer on otherhosts

Network Model Concepts

A networking model refers to a common structure that enables

communication between two or more systems

Networking models consist of layers You can think of layers as a series ofsteps or functions that must be sequentially completed for communication

to occur between two systems

The following mapping helps you better understand the network model:

● Model = structure

● Layer = functions

● Protocol = rules

Advantages of Using a Layered Model

Some of the advantages of a layered model are that it:

● Divides the complexity of networking into many functions or layers

● Enables you to introduce changes or new features in one layer

without having to change the other layers

● Provides a standard to follow, allowing inter-operability betweensoftware and hardware vendors

● Simplifies troubleshooting

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Introducing the Layers of the TCP/IP Model

Table 1-1 shows that the TCP/IP model is a four-layered structure resting

on a common hardware platform The TCP/IP model was developed bythe Department of Defense (DOD) in 1979 It has standards that aredefined and described in Request for Comment (RFC) documents

RFCs are a frame of reference for describing the protocol architecture andfunctions specific to the TCP/IP protocol stack For a complete listing ofRFCs, visit http://www.ietf.org/rfc.html

Table 1-1 TCP/IP Network Model TCP/IP Layer Description

Application ● Consists of user-accessed application programs

and network services

● Defines how cooperating networks representdata

Transport ● Manages the transfer of data by using

acknowledged and unacknowledged transportprotocols

● Manages the connections between cooperatingapplications

Internet ● Manages data addressing and delivery between

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Network Interface Layer

Figure 1-2 shows the Network Interface layer The primary functions ofthis layer are:

● Managing the delivery of data across the physical network

● Detecting errors

● Framing packets

Figure 1-2 TCP/IP Network Interface Layer

The Network Interface layer services the Internet layer by providingcommunication between nodes on the same network This layer defineshow bits are assembled into manageable units of data A packet data unit(PDU) is a series of bits with a well-defined beginning and a well-definedend Figure 1-3 shows a specific type of PDU known as an Ethernet frame,where the bits are divided into fields containing information labels, such

as preamble, destination and source hardware address, frame length ortype, data, and cyclic redundancy check (CRC)

Figure 1-3 Structure of a Frame

Hardware Layer

TCP/IP Layers Application Layer Transport Layer Internet Layer

Network Interface Layer

Packet

data unit

Preamble DestinationAddress AddressSource Type Data CRC

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Examples of Network Interface layer protocols are:

● Institute of Electrical and Electronics Engineers (IEEE) 802.3 –Ethernet standards

● IEEE 802.4 – Token bus standards

● IEEE 802.5 – Token ring standards

Internet Layer

The Internet layer attempts to ensure that messages reach theirdestination system using the most efficient route Figure 1-4 shows thelocation of this layer The primary functions of the Internet layer are:

● Fragmenting and reassembly of data

● Routing data

Figure 1-4 TCP/IP Internet Layer

Using a routing table, the Internet layer determines the next directlyaccessible node in route to the packet’s destination This node is either thedestination itself or the most immediate gateway to the destination TheInternet layer uses the Internet Protocol (IP) and Internet Control MessageProtocol (ICMP) The IP is responsible for fragmenting and routing data,while ICMP assists routing, and performs error detection and othernetwork management tasks IP encapsulates data into datagrams, which

in turn are encapsulated inside Network Interface layer PDUs

Hardware Layer

TCP/IP Layers Application Layer Transport Layer

Internet Layer

Network Interface Layer Datagram

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Transport Layer

The Transport layer manages the transfer of application data betweencommunication hosts It also controls the flow of data and defines thetransport quality of the data transmission Figure 1-5 shows the location

of the Transport layer

Figure 1-5 TCP/IP Transport Layer

The mechanisms used by the Transport layer to determine whether datahas been correctly delivered are:

● Acknowledgement responses

● Sequencing

● Flow control

The Transport layer facilitates end-to-end data transfer It supports

multiple operations simultaneously The layer is implemented by twoprotocols: the Transmission Control Protocol (TCP) and the User

Datagram Protocol (UDP) TCP uses packets called segments, while UDPuses packets called datagrams Both TCP and UDP are encapsulatedinside Internet layer datagrams for transmission to the next node

Hardware Layer

TCP/IP Layers Application Layer

Transport Layer

Internet Layer Network Interface Layer

Segment

or

datagram

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The Transport layer facilitates two types of communication:

● Connection-oriented (TCP) – A connection must be established at theTransport layer of both systems before the application can transmitany data

● Connectionless (UDP) – All systems do not need to establish aconnection with the recipient prior to data exchange

TCP is a more reliable form of data exchange than UDP

Application Layer

The top layer of TCP/IP is the Application layer Figure 1-6 shows thelocation of this layer

Figure 1-6 TCP/IP Application Layer

The Application layer includes all the processes that use Transport layerprotocols to deliver data to the Internet layer There are many applicationprotocols, and new protocols are frequently added

Some common TCP/IP applications include:

● Telnet Protocol

● File Transfer Protocol (FTP)

● Simple Network Management Protocol (SNMP)

● Simple Mail Transfer Protocol (SMTP)

Stream or message

Hardware Layer

TCP/IP Layers

Application Layer

Transport Layer Internet Layer Network Interface Layer

Tiêu đề	Network Administration for the Solaris 9 Operating Environment SA-399 Student Guide
Trường học	Sun Microsystems, Inc.
Chuyên ngành	Network Administration
Thể loại	hướng dẫn
Năm xuất bản	2002
Thành phố	Broomfield

Định dạng
Số trang	60
Dung lượng	564,04 KB