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Planning GuideChapter 2: Configure a Network Operating System

CCENT Routing and SwitchingIntroduction to Networks v6.0Instructor Planning Guide

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Instructor Materials – Chapter 2 Planning Guide This PowerPoint deck is divided in two parts: Instructor Planning Guide

• Information to help you become familiar with the chapter• Teaching aids Instructor Class Presentation

• Optional slides that you can use in the classroom• Begins on slide # 15 Note: Remove the Planning Guide from this presentation before sharing with anyone.

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Chapter 2: Activities What activities are associated with this chapter?

Page # Activity Type Activity Name Optional?

2.0.1.2 Class Activity It is Just an Operating System Optional

2.1.4.6 Packet Tracer Navigating the IOS Optional

2.1.4.7 Lab Establishing a Console Session with Tera Term Recommended

2.2.3.4 Packet Tracer Configuring Initial Switch Settings Recommended

2.3.2.5 Packet Tracer Implementing Basic Connectivity Recommended

2.3.3.3 Lab Building a Simple Network Optional

2.3.3.4 Lab Configuring a Switch Management Address Recommended

2.4.1.1 Class Activity Tutor Me Optional

2.4.1.2 Packet Tracer Skills integration Challenge Recommended

The password used in the Packet Tracer activities in this chapter is: PT_ccna5

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Chapter 2: Assessment Students should complete Chapter 2 assessment after completing Chapter 2. Quizzes, labs, Packet Tracers and other activities can be used to informally assess student

progress. Feel free to also add your own assessments and labs.

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Chapter 2: Best Practices Prior to teaching Chapter 2, the instructor should complete the Chapter 2 assessment. The objectives of this chapter are:

• Explain the purpose of the Cisco IOS. • Explain how to access a Cisco IOS device for configuration purposes.• Explain how to navigate Cisco IOS to configure network devices.• Describe the command structure of the Cisco IOS software.• Configure hostnames on a Cisco IOS device using the CLI.• Use Cisco IOS commands to limit access to device configurations.• Use Cisco IOS commands to save the running configuration.• Explain how devices communicate across network media.• Configure a host device with an IP address.• Verify connectivity between two end devices.

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Chapter 2: Best Practices (Cont.) Create a Packet Tracer with a switch (int vlan 1 configured) and a router (int g0/0

configured) so the demonstration can be used throughout the chapter. Chapter appendix includes a video that introduces Cisco Connection Online.

- Make sure all students have a CCO account before the end of course 1, but make sure they realize they will not be able to download an IOS without a SMARTNET account.

- A CCO account can also be used to access additional materials at: learningnetwork.cisco.com

- Teachers can download an IOS with a Netacad Maintenance agreement. More information can be found on NetSpace (netacad.com) > PROGRAM> EQUIPMENT> NETACAD MAINTENANCE.

Explain that the IOS gives networking hardware its capabilities.

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Chapter 2: Best Practices (Cont.)Recommend software and hardware: TeraTerm Download – http://logmett.com/index.php?/download/free-downloads.html PuTTY Download – http://www.putty.org/ HyperTerminal Download – https://www.hilgraeve.com/hyperterminal/ Mini-USB Console Cable – Driver is needed

(http://software.cisco.com/download/release.html?mdfid=282774238&flowid=714&softwareid=282855122&release=3.1&relind=AVAILABLE&rellifecycle=&reltype=latest) and USB to mini-USB cables are needed. Air Console allows any Wi-fi or Bluetooth device to connect to the serial port –

https://www.get-console.com/shop/en/27-airconsole USB to RJ-45 Console Cable – https://www.amazon.com/Console-Essential-Accesory-

Ubiquity-Switches/dp/B01AFNBC3K

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Chapter 2: Best Practices (Cont.) Explain to the students that this chapter covers three basic concepts required for setting up

and testing a network:- Before configuring devices, you must know the functions of the Cisco IOS devices,

learn how to communicate with the IOS, and learn how to physically connect to the devices.

- Know the basics of device configurations, including securing the device, naming devices, and enabling interfaces.

- Know the basic tools for verifying network connectivity, such as ping and traceroute. Ensure the class knows that a router or a switch runs an IOS. Ask volunteers to explain

how access is gained to the IOS.- Devices can be accessed via the console port (a direct physical connection), via Telnet,

SSH (a virtual connection), HTTP, or via AUX (telephone modem or ISDN)

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Chapter 2: Best Practices (Cont.) Write the following configuration modes on the board and ask the class to explain or define

these modes:- user EXEC mode- privilege EXEC mode- global configuration mode

Explain to the class that devices come with default names.- Explain that names are not assigned randomly. For example, a router is named “router”

by default and a switch is “switch”. - User show running-configuration to see the configuration statement “hostname switch”

or “hostname router”.- A networking professional creates a naming convention that spans the company to

maintain continuity and prepare for future growth.

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Chapter 2: Best Practices (Cont.) ? is a KEY to IOS survival. Teach the students that ? is your friend! Students need to be aware of error messages when working in the CLI. When a user presses Enter to complete a command, check to make sure the command

was accepted. Display a router interface and demonstrate the modes and their associated prompts. Demonstrate how to back out from privilege EXEC mode to user EXEC mode with the

disable command. Demonstrate the various forms of context-sensitive Help available. Demonstrate, with a preconfigured configuration, an end-to-end connection with ping and

traceroute. Reinforce that show commands serve as powerful troubleshooting tools.

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Chapter 2: Best Practices (Cont.) Make sure students understand “delimiting character”. Explain that other than physical security of equipment, which is always necessary, there

are also ways to use passwords to add additional security. On the board, write the four password types students will learn to configure in the PT Activity.

- console password – Password to limit device access using the console connection.- enable password – Password to limit access to the privileged EXEC mode.- enable secret password – Encrypted password to limit access to the privileged EXEC

mode.- VTY password – Password to limit device access using Telnet.

Emphasize the use of the copy running-config startup-config or copy run start commands.

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Chapter 2: Best Practices (Cont.) Emphasize to students that they can use the show run command to see commands, such

as hostname and line console 0. Explain that there are two types of configuration files:

- Startup configuration files (startup-config) - These are stored in NVRAM and remain intact if the router is powered off.

- Running configuration file (running-config) - Each time a router is booted up, the startup-config is loaded into RAM and becomes the second type of config file, which is the running configuration file. This file will change immediately if an administrator makes a change to a device. This change will cause the running-config to be different from the startup-config. Because the running-config is stored in RAM, if a power cycle takes place without saving the changes from running-config to the startup-config, any changes made will be lost.

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Chapter 2: Best Practices (Cont.) Write the following definitions on the board and then ask the students to name the

command.• Shows the config file in RAM. (show running-config)• This file is immediately changed if you make any changes to the router. (running-config)• This file is in NVRAM and will become the running-config in the event of a power cycle.

(startup-config)• Copies the current configuration in RAM to NVRAM. (copy running-config startup-

config)• Causes the device to reload the startup-config into RAM. (reload) Mention to the students that a text file created can be used as a record of how the device is

currently implemented and be used to restore a configuration. • The file would require editing before being used to restore a saved configuration to a

device.• For instance, interfaces have to be re-enabled using the no shutdown command.

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Chapter 2: Additional Help For additional help with teaching strategies, including lesson plans, analogies for difficult

concepts, and discussion topics, visit the CCNA Community at: https://www.netacad.com/group/communities/community-home Best practices from around the world for teaching CCNA Routing and Switching.

https://www.netacad.com/group/communities/ccna-blog If you have lesson plans or resources that you would like to share, upload them to the

CCNA Community in order to help other instructors. Students can enroll in Packet Tracer Know How 1: Packet Tracer 101 (self-enroll)

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Chapter 2:Configuring a Network Operating System

CCENT Routing and SwitchingIntroduction to Networks v6.0

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2.1 IOS BOOTCAMP

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Chapter 2 - Sections & Objectives 2.1 IOS Bootcamp

• Explain the purpose of Cisco IOS.• Explain how to access a Cisco IOS device for configuration purposes.• Explain how to navigate Cisco IOS to configure network devices.• Describe the command structure of Cisco IOS software. 2.2 Basic Device Configuration

• Configure hostnames on a Cisco IOS device using the CLI.• Use Cisco IOS commands to limit access to device configurations.• Use IOS commands to save the running configuration. 2.3 Address Schemes

• Explain how devices communicate across network media.• Configure a host device with an IP address.• Verify connectivity between two end devices.

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Key Components of a 2950 or 2960 Switches 12, 24, or 48 10/100 Ethernet Ports Port Status LEDs Mode Button (SYST, RPS, Port) Console port Dual Purpose 10/100/1000

or SFP port(s) Cisco IOS software

Port Status:•Off: No link, or port was administratively shut down

•Green: Link present•Blinking green: Port is transmitting or receiving data

•Alternating green/amber: Link fault•Amber: Port is blocked by Spanning Tree Protocol (STP) and is not forwarding data

•Blinking amber: Port Is blocked by STP and is transmitting or receiving packets

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Routers Cisco 1841

Cisco 1941

Cisco 4321

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Cisco IOS Operating Systems

• PC OS allows users to interact with the computer• User-computer interaction in PC OSs are often done via mouse, keyboard and monitor• Cisco IOS is also an Operating System• Cisco IOS allows users to interact with Cisco devices. Cisco devices use the Cisco Internetwork Operating System (IOS).

• Although used by Apple, iOS is a registered trademark of Cisco in the U.S. and other countries and is used by Apple under license.

• The kernel provisions hardware resources to meet software requirementsOS Shell• The OS shell is either a command-line interface (CLI) or a graphical

user interface (GUI) and enables a user to interface with applications.

OS Kernel• The OS kernel communicates directly with the hardware and manages

how hardware resources are used to meet software requirements.

Hardware• The physical part of a computer including underlying electronics.

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Purpose of OS Cisco IOS enables a technician to:

• Use a keyboard to run CLI-based network programs.• Use a keyboard to enter text and text-based commands.• View output on a monitor. Switch or router IOS provides options to:

• Configure interfaces• Enable routing and switching functions All networking devices come with a default IOS There are many distinct variations of Cisco IOS:

• IOS for switches, routers, and other Cisco networking devices• IOS numbered versions for a given Cisco networking devices Possible to upgrade the IOS version or feature set if you know:

• Models number• Amount of RAM and flash memory• What features are required (feature set)

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Purpose of OS All devices come with a default IOS

and feature set. It is possible to upgrade the IOS version or feature set. An IOS can be downloaded from

cisco.com. However, a Cisco Connection Online (CCO) account is required. Note: The focus of this course will

be on Cisco IOS Release 15.x.

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Console Access Method Most common methods to access the Command Line Interface:

• Used for initial configuration, use the console port to locally access the switch or router from a serial or USB interface of the PC

• Device is accessible even if no networking services have been configured (out-of-band)• Need a special console cable• Allows configuration commands to be entered• Should be configured with passwords to prevent unauthorized access• Device should be located in a secure room so console port can not be easily accessed• Displays startup, debugging, and error messages by default

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Telnet, SSH, and AUX Access Methods Telnet

• Method for remotely accessing the CLI over a network• Require active networking services and one active interface that is configured Secure Shell (SSH)

• Remote login similar to Telnet but utilizes more security• Stronger password authentication• Uses encryption when transporting data• Used to keep the user ID, password, and session contents private when establishing

remote CLI connectivity Auxiliary Port

• Out-of-band connection• Uses telephone line (dialup)• Can be used like console port• Not supported on Catalyst switches

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Terminal Emulation Programs Regardless of access method, a terminal emulation program will be required. Software available for connecting to a networking device

• PuTTY• Tera Term• HyperTerminal• SecureCRT• OS X Terminal

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Cisco IOS Modes of Operation The Cisco IOS modes use a hierarchical command structure. Each mode has a distinctive prompt and is used to accomplish particular tasks with a

specific set of commands that are available only to that mode. Initial configuration must be done via console

connection, locally accessed through a serial or USB interface of a PC Configuration is then done via various CLI

command modes

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Primary Command Modes The User EXEC mode allows only a limited number of basic monitoring commands

• Often referred to as view-only mode• By default, there is no authentication required to access the user EXEC mode but

it should be secured. The Privileged EXEC mode, by default, allows execution of all monitoring,

configuration, and management commands.• Often referred to as “enable mode” because it requires the enable user EXEC

command.• By default, there is no authentication required to access the user EXEC mode but

it should be secured. Prompt changes denoting the current CLI mode

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Configuration Command Modes Configuration Command Modes

• The Configure Terminal command enters the Global Configuration Mode• Global Configuration is the primary configuration mode• Examples are: Router(config-line)# and switch(config-if)#• Sub-configuration modes are accessible from the Global Configuration Mode• Each of these modes allows the configuration of a particular part

or function of the IOS device- Interface mode - to configure one of the network interfaces.- Line mode - to configure the console, AUX, Telnet, or

SSH access Navigate Between IOS Modes

• Navigation between modes is also done via commands• The enable command enters the Privileged EXEC Mode• The exit commands exits to the parent command mode

(returns to the previous level)• Ctrl+z - Works the same as end

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IOS Command Structure Basic IOS Command Structure

• A Cisco IOS device supports many commands. Each IOS command has a specific format or syntax and can only be executed at the appropriate mode.

• The general syntax for a command is the command followed by any appropriate keywords and arguments.

• Keyword - a specific parameter defined in the operating system• Argument - not predefined; a value or variable defined by the user IOS Command Syntax

• Provides the pattern or format that must be used when entering a command.• The Cisco IOS Command Reference is the ultimate source of information for a particular

IOS command.

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Context Sensitive Help (?) Context-sensitive help provides a list of commands and the arguments associated with

those commands within the context of the current mode.• Displays a list of all available commands within the current mode• The IOS has two forms of help available: Context-Sensitive Help and Command Syntax

Check.• Determines which option, keyword, or argument is available for the entered command• To access context-sensitive help, enter a

question mark ?, at any prompt

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Command Syntax Check Commands and keywords can be shortened to the minimum number of characters that

identify a unique selection. The command line interpreter checks an entered command from left to right to determine

what action is being requested. If the interpreter understands the command, the requested action is executed and the CLI

returns to the appropriate prompt. If the interpreter discovers an error, the IOS generally provides feedback such as

“Ambiguous command”, “Incomplete command”, or “Incorrect command”.

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Hot Keys and Shortcuts Line editing keyboard shortcuts:

• Down Arrow - Allows the user to scroll forward through former commands• Up Arrow - Allows the user to scroll backward through former commands• Tab - Completes the remainder of a partially typed command or keyword• Ctrl-A – Moves cursor to the beginning of the line• Ctrl-C - Aborts the current command and exits the configuration mode• Ctrl-E – Moves to the end of the line.• Ctrl-R - Redisplays a line• Ctrl-Z - Exits configuration mode and returns to user EXEC• Ctrl-Shift-6 - Allows the user to interrupt or abort an IOS process such as ping

or traceroute. • Space bar – Displays the next screen• ? – Provides context-sensitive help

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Router Configuration Sources RAM – holds active/running configuration. Contents are lost with power down. NVRAM – holds startup configuration. Retains contents when power is removed. Flash – holds IOS images. Similar to NVRAM. ROM – holds bootstrap and POST. Has basic IOS in case no full IOS is found.

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Location of the Cisco IOS IOS stored in Flash Non-volatile storage – not lost when power is lost Can be changed or overwritten as needed Can be used to store multiple versions of IOS IOS copied from flash to volatile RAM Quantity of flash and RAM memory determines IOS that can be used

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The ROM modes allow a user to recover a password by changing the registry settings, to replace the Cisco IOS image file, or recover from system failures

3 Modes in the IOS

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Before anything else happens, there is a Power On Self-Test (POST)

Step 1 Bootstrap loader in ROM executes

Step 3

Step 2 IOS loads

The configuration file is loaded

A Router Starts Up

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A.B.C.

A.

B.

C.

Steps in Router Initialization

ROM Basic IOS Rom Monitor Mode

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2.2 BASIC DEVICE CONFIGURATION

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IOS Examination Commands

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The show version Command

IOS version

Boot ROM version

Router up time

Last restart method

Location and System image filename

# & type of interfaces on the router

Bootstap ROM version

Platform

Configuration register setting

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The show flash Command This command would show all of the Cisco IOS image files – not just the one that the router

booted from Might compare to a directory listing

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Device (Host) Names Device Names

• Hostnames allow devices to be identified by network administrators over a network or the Internet

• Without names, network devices are difficult to identify for configuration purposes• Very important and should also be displayed in the topology Hostname naming conventions guidelines:

- Start with a letter- Contain no spaces- End with a letter or digit- Use only letters, digits, and dashes (- or _)- Be less than 64 characters in length

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1. Hostnames Hostnames allow devices to be identified by

network administrators over a network or the Internet. Used to identify the device during remote access

(SSH or telnet). Commands:

• hostname• no ip domain-lookup

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Banner Messages banner motd command

• Displays a message when a user accesses a router or switch

• Important part of the legal process in the event that someone is prosecuted for breaking into a device

• Wording that implies that a login is "welcome" or "invited" is not appropriate

• Often used for legal notification because it is displayed to all connected terminals

• To test whether the banner is properly configured type exit from user mode and then press Enter.

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Step 1 - Secure network devices to physically limit access by placing them in wiring closets and locked racks. Step 2 - Enforce secure passwords as passwords are the primary defense against

unauthorized access to network devices.

Limiting Device Access

Limit administrative access as follows. Use strong password as suggested.

For convenience, most labs and examples in this course use the simple but weak passwords cisco or class.

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Limit Access to Device Configurations Cisco IOS displays passwords in plain text by default The service password-encryption command enhances password security on Cisco

routers and switches by encrypting all passwords that are stored in router or switch configuration files Secure Device Access

• Secure privileged EXEC and user EXEC access with a password.• Secure virtual terminal lines with a password Configure Passwords

• Use strong passwords• Avoid re-using passwords Encrypt Passwords

• Passwords should be encrypted usingservice password-encryption

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2. Passwords Modes and interfaces that can be protected with passwords:

• Enable password - Limits access to the privileged EXEC mode• Enable secret - Encrypted, limits access to the privileged EXEC mode• Console password - Limits device access using the console connection• VTY password - Limits device access over Telnet• Auxiliary password - Limits device access using the auxiliary connection• Logging synchronous – Keeps the command on the same line as console messages appear

Note: We will use passwords: cisco or class

Router(config)#enable password ciscoRouter(config)#enable secret classRouter(config)#

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Securing User EXEC Access Console port must be secured

• Reduces the chance of unauthorized personnel physically plugging a cable into the device and gaining device access

vty lines allow access to a Cisco device via Telnet• Requires an active Internet connection• Number of vty lines supported varies with the type of device and the IOS version

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Securing Privileged EXEC Access enable secret

• Secure access to Privileged EXEC mode• Provides greater security because the password is encrypted

enable password• Not commonly used anymore

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Encrypting Password Display service password-encryption

• Prevents passwords from showing up as plain text when viewing the configuration

• Purpose of this command is to keep unauthorized individuals from viewing passwords in the configuration file

• Once applied, removing the encryption service does not reverse the encryption

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3. Interfaces interface serial 0/0/0

• ip address address subnetmask• clock rate 56000 (DCE only)• description your own text• no shutdown

Other common interfaces:• serial 0/0/1• fastEthernet 0/0• fastEthernet 0/1• loopback 0

Router(config)# interface serial 0/0/0Router(config-if)# ip address 199.17.36.33 255.255.255.224Router(config-if)# clock rate 56000Router(config-if)# description * Link to Router 2 *Router(config-if)# no shutdownRouter(config-if)#

Router# show runinterface Serial0/0/0description * Link to Router 2 *ip address 199.17.36.33 255.255.255.224clock rate 56000

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4. Protocols router rip

• network network address

Other router protocols• igrp• eigrp• ospf• is-is• bgp

Router(config)#router ripRouter(config-router)#network 199.17.36.32Router(config-router)#network 1.1.1.1

Router(config)# do show runrouter ripnetwork 1.0.0.0network 199.17.36.0

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5. IP Hosts Optional step Names are only locally significant Faster and more convenient than ip addresses Can assign multiple addresses Command:

• ip hosts name interface-addresses

R1(config)#R1(config)#ip host R1 1.1.1.1 192.168.37.2 20.20.20.33R1(config)#ip host R2 2.2.2.2 192.168.37.3 21.21.21.33R1(config)#ip host R3 3.3.3.3 192.168.38.2R1(config)#

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Save Configurations Save the Running Configuration File

• File stored in NVRAM that contains all of the commands that will be used upon startup or reboot

• NVRAM does not lose its contents when the device is powered off. After the Running Configuration

• File stored in RAM that reflects the current configuration, modifying affects the operation of a Cisco device immediately.

• RAM loses all of its content when the device is powered off or restarted. Issue the reload command without saving the

running configuration to discard the changes and work with the original file in NVRAM

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Connect to the switch using PuTTY or Tera Term.

Enable logging and assign a name and file location to save the log file.

Generate text to be captured as text displayed in the terminal window will also be placed into the chosen file.

Disable logging in the terminal software by choosing None in the Session logging option.

Capture Configuration to a Text File Configuration files can also be saved and archived to a text document for editing or reuse

later. For example, assume a switch has been configured and the running config has been saved.

Execute the show running-config or show startup-config command at the privileged EXEC prompt.

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Capture Configuration to a Text File Configuration files can also be saved and archived to a text document The configuration can then be edited with any text editor and placed back in the device

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6. Verify and Save The running configuration affects the operation of the device immediately when modified Commands:

• show run – examine the contents of the current configuration running in RAM• show startup-config – examine the contents of the saved configuration in the

NVRAM• show interfaces [s 0/0/0]• show ip interface brief• show ip route• show cdp neighbors [detail]• show controllers [s 0/0/0]• ping address• telnet address• copy running-config startup-config

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The show interfaces Command

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The show ip interface brief Command Factors that can be determined from the output of the show ip interface brief command:

Router Switch

• Available interfaces• Interface/Port status• Protocol status• Interface/Port IP address

• Available interfaces• Interface/Port IP address• Interface/Port status – devices attached to a

physical interface • The switch can be remotely managed• The default SVI is configured

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The show ip route Command Displays routing table information about all known networks and subnets

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The show cdp neighbors Commands Information gathered by CDP includes:

• Device identifiers - configured host name• Address list - Layer 3 address, if configured• Port identifier - directly connected port• Capabilities list - function or functions provided by the device • Platform - hardware platform of the device

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Configuration FilesSwitch# reloadSystem configuration has been modified. Save? [yes/no]: nProceed with reload? [confirm] Startup configuration is removed by using the erase

startup-configSwitch# erase startup-config On a switch you must also issue the delete vlan.datSwitch# delete vlan.datDelete filename [vlan.dat]?Delete flash:vlan.dat? [confirm]

The running configuration (RAM) affects the operation of the device immediately when modified. Issue the reload command without saving the running configuration to discard the changes

and work with the file in NVRAM.

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Basic Router Setupconf thostname R1enable secret classenable password ciscono ip domain-lookupservice password-encryptionbanner motd $ Welcome to router R1 $cdp runline con 0password ciscologging synchronousloginline vty 0 4password ciscologging synchronousloginexitinterface Loopback0ip address 1.1.1.1 255.255.255.255

interface FastEthernet0/0ip address 197.63.58.65 255.255.255.192no shutdowninterface Serial0/0/0description R1 s0/0/0 to R2 s0/0/1ip address 155.6.0.1 255.255.255.252clock rate 56000no shutdownexitrouter ripnetwork 1.1.1.1network 155.6.0.0network 197.63.58.64exitip host r1 1.1.1.1 197.63.58.65ip host r2 2.2.2.2 198.65.72.97ip host r3 3.3.3.3 199.197.50.65endcopy run start

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DHCP Server CommandsRouter1>enableRouter1#config tRouter1(config)#ip dhcp pool MYPOOLRouter1(dhcp-config)#network 172.16.0.0 255.255.0.0Router1(dhcp-config)#dns-server 172.16.1.103 172.16.2.103Router1(dhcp-config)#default-router 172.16.1.100Router1(dhcp-config)#lease 7 8 30Router1(dhcp-config)#exitRouter1(config)#ip dhcp excluded-address 172.16.1.100 172.16.1.103

show ip dhcp bindings

Lowest IP Address Highest IP Address

Network Address

Descriptive Name

Default-Gateway

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NAT Commands (Static) Router1>enableRouter1#config tRouter1(config)#interface fastethernet 0/0Router1(config-if)#ip address 172.32.232.1 255.255.555.0Router1(config-if)#ip nat insideRouter1(config-if)#exitRouter1(config)#interface serial 0/0Router1(config-if)#ip address 209.165.201.1 255.255.255.252Router1(config-if)#ip nat outsideRouter1(config-if)#exitRouter1(config)#ip nat inside source static 172.31.232.14 209.165.201.1Router1(config)#exit

show ip nat statistics show ip nat translations

Computer’s IP Address

Serial Port’s IP Address

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Configuring a Switch Virtual Interface A virtual interface allows remote management of a Layer 2 switch VLAN 1 is the default Switch Virtual Interface (SVI) on a Cisco switch Configuration commands:

• interface vlan 1 - interface configuration mode • ip address 192.168.10.2 255.255.255.0 - configures the IP address and subnet

mask for the switch • no shutdown - administratively enables the interface• ip default-gateway 192.168.10.220 – tells the switch where to send data destine

for the Internet Switch still needs to have physical ports configured and VTY lines to enable remote

management Vlan 1 is not an actual physical interface but a virtual one

no shutdown

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Basic Switch Setup config t hostname S1 enable secret class enable password cisco no ip domain-lookup banner motd $Welcome to switch S1$ cdp run line con 0 password cisco logging synchronous login

line vty 0 15 password cisco logging synchronous login exit interface vlan1 ip address 197.63.58.126 255.255.255.192 no shutdown exit ip default-gateway 197.63.58.65 end copy run start

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2.3 ADDRESS SCHEMES

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Ports and Addresses IP Addresses

• Each end device on a network must be configured with an IP address.• Enable devices to establish end-to-end communication on the Internet.• The structure of an IPv4 address is called dotted decimal notation and is represented by

four decimal numbers between 0 and 255. • IPv6 is the most recent version of IP and the replacement for the more common IPv4. Interface and Ports

• Network communications depend on interfaces and the cables that connect them.• Different types of network media have

different features and benefits.• Ethernet is the most common local area

network (LAN) technology.• SVI provides a means to remotely manage

a switch over a network.

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Configure Device IP Addressing Manual IP Address Configuration for End Devices

• To manually configure an IPv4 address on a Windows host, open the Control Panel > Network Sharing Center > Change adapter settings and choose the adapter.

• Next right-click on the adaptor and select Properties to display the Local Area Connection Properties

• Choose IPv4 address and click Properties Each end device on a network (e.g., PCs, laptops, servers,

printers, VoIP phones, security cameras, …) require an IP configuration consisting of:• IP address• Subnet mask• Default gateway (optional for some devices) IPv4 addresses are displayed in dotted decimal format:

• 4 decimal numbers 0 and 255• Separated by decimal points (dots)• E.g., 192.168.1.10, 255.255.255.0, 192.168.1.1

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IP Address Configuration for End Devices Automatic IP Address Configuration for End Devices

• Dynamic Host Control Protocol (DHCP) enables automatic IPv4 address configuration for every end device that has DHCP enabled. No extra configuration is needed.

• With DHCP, hosts can connect to the network and get an IP address without manual configuration.

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Examining a PC’s IP configuration ipconfig

• Used on a Windows PC to see the basic IP configuration of that computer- IP address- Subnet Mask- Default Gateway

• Each IP address must be unique within the local network (LAN) ipconfig /all

• More details about each connection:- MAC addresses- DNS servers

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Testing End-to-End Connectivity Interface Addressing Verification

• Cisco IOS supports commands to allow IP configuration verification. End-To-End Connectivity Test

• The ping command can be used to test connectivity to another device on the network or a website on the Internet.

Ping tests connectivity with the destination device• Ping 127.0.0.1• Ping NIC IP address• Ping default gateway• Ping next hop• Ping next interface• Ping end device

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CHAPTER TERMS

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Section 2.1 New Terms and Commands kernel shell Command-line interface (CLI) Graphical user interface (GUI) Cisco IOS Firmware Console Out-of-band SSH Telnet Auxiliary port (AUX) PuTTY Tera Term Command Syntax Check CLI Hot Keys and Shortcuts

Hostnames SecureCRT OS X Terminal Cisco IOS modes User EXEC mode Privileged EXEC mode Global Configuration Mode Line configuration mode Interface configuration mode enable command disable command exit command end command Key combination – Ctrl+Z Context-Sensitive Help

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Section 2.2 New Terms and Commands hostname name Strong passwords Startup configuration Random Access Memory (NVRAM) Running configuration Random Access Memory (RAM)

enable secret class line console 0 password cisco login line vty 0 15 service password-encryption banner motd # the message of the day # show running-config copy running-config startup-config reload

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Section 2.3 New Terms and Commands IPv4 address Subnet mask Default gateway Physical ports Virtual interface Copper Fiber Optics Wireless Ethernet Local Area Network (LAN) Layer 2 switch Layer 3 addresses Switch virtual interface (SVI)

Dynamic Host Configuration (DHCP) Domain Name System (DNS) ipconfig command prompt interface vlan 1

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