chapter 2

To exit a sub-configuration mode and return to global configuration mode

use the exit command. Notice the changes in the command prompt.

PCs typically default to using ____ for automatic IPv4 address configuration.

DHCP

Enter line console configuration mode using the ____ global configuration command

line console 0,

enable user EXEC access using the ___ command

login

To remove the configured hostname and return the switch to the default prompt, use the ___ global config command.

no hostname

enable the virtual interface using the ___ interface configuration command.

no shutdown

OS

operating system

To configure the device, the user must enter

Global Configuration Mode

Secure Shell (SSH

SSH is a method for remotely establishing a secure CLI connection through a virtual interface, over a network. Unlike a console connection, SSH connections require active networking services on the device including an active interface configured with an address.

securing administrative access

Secure privileged EXEC access with a password Secure user EXEC access with a password Secure remote Telnet access with a password Encrypt all passwords Provide legal notification

Telnet

Telnet is an insecure method of remotely establishing a CLI session through a virtual interface, over a network. Unlike SSH, Telnet does not provide a securely encrypted connection. User authentication, passwords, and commands are sent over the network in plaintext.

ping ip-address

The command is ping and the user-defined argument is the ip-address of the destination device. For example, ping 10.10.10.5.

traceroute ip-address

The command is traceroute and the user-defined argument is the ip-address of the destination device. For example, traceroute 192.168.254.254.

startup-config

The file stored in Non-volatile Random Access Memory (NVRAM) that contains all of the commands that will be used by the device upon startup or reboot. NVRAM does not lose its contents when the device is powered off.

running-config

The file stored in Random Access Memory (RAM) that reflects the current configuration. Modifying a running configuration affects the operation of a Cisco device immediately. RAM is volatile memory. It loses all of its content when the device is powered off or restarted.

User EXEC Mode

This mode has limited capabilities but is useful for basic operations. It allows only a limited number of basic monitoring commands but does not allow the execution of any commands that might change the configuration of the device. The user EXEC mode is identified by the CLI prompt that ends with the > symbol.

Privileged EXEC Mode

To execute configuration commands, a network administrator must access privileged EXEC mode. Higher configuration modes, like global configuration mode, can only be reached from privileged EXEC mode. The privileged EXEC mode can be identified by the prompt ending with the # symbol.

Line Configuration Mode

Used to configure console, SSH, Telnet, or AUX access.

For example, the configure command can be shortened to

conf because configure is the only command that begins with conf.

To move in and out of global configuration mode, use the

configure terminal privileged EXEC mode command

If power to the device is lost or if the device is restarted, all configuration changes will be lost unless they have been saved. To save changes made to the running configuration to the startup configuration file use the ___ privileged EXEC mode command.

copy running-config startup-config

For example, entering the command, description Connects to the main headquarter office switch,

describes where the other device is at the end of the connection.

For instance, the syntax for using the description command is

description string.

Use the ____ privileged EXEC mode command to return to user EXEC mode.

disable

Context-sensitive help

enables you to quickly find which commands are available in each command mode, which commands start with specific characters or group of characters, and which arguments and keywords are available to particular commands. To access context-sensitive help, simply enter a question mark, ?, at the CLI.

To move from any sub-configuration mode to the privileged EXEC mode,

enter the end command or enter the key combination Ctrl+Z.

To move from any sub-configuration mode of the global configuration mode to the mode one step above it in the hierarchy of modes,

enter the exit command.

To return to the privileged EXEC mode

enter the exit global config mode command.

The startup configuration is removed by using the ___ privileged EXEC mode command

erase startup-config

From global configuration mode, enter the command ____ followed by the ____.

hostname, name of the switch and press Enter

The description command is typically used to

identify the purpose of an interface.

To configure an SVI on a switch, use the ___ global configuration command

interface vlan 1

assign an IPv4 address using the ___ ip-address subnet-mask interface configuration command.

ip address

you use commands and utilities like ___ to verify a PC host's network configuration

ipconfig

To secure VTY lines used for SSH and Telnet, enter line VTY mode using the

line vty 0 15 global config command

Argument

not predefined; a value or variable defined by the user (in the figure, 192.168.10.5)

specify the VTY password using the ___ password command.

password

IP addresses can be assigned to both

physical ports and virtual interfaces on devices *A virtual interface means that there is no physical hardware on the device associated with it.

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

ping

shell

portion that interfaces with applications and the user

The most important password to configure is access to the ____ To secure privileged EXEC access, use the ____ password global config command

privileged EXEC mode, enable secret

you can restore the device to its previous configuration by removing the changed commands individually or reload the device using the ___ privileged EXEC mode command to restore the startup-config.

reload

Virtual terminal (VTY) lines enable

remote access to the device

To encrypt passwords, use the ___ global config command

service password-secret *This encryption applies only to passwords in the configuration file, not to passwords as they are sent over the network. The purpose of this command is to keep unauthorized individuals from viewing passwords in the configuration file.

the ___ command. This command is useful for verifying the condition of the switch interfaces.

show ip interface brief

Use the ___ command to verify that passwords are now encrypted.

show running-config

use the ___ privileged EXEC mode command to view the running configuration file. To view the startup configuration file, use the ___ privileged EXEC command.

show running-config, show startup-config

from the privileged EXEC mode, access the global configuration mode by entering

the configure terminal command.

To secure the user EXEC access,

the console port must be configured

When configuring a networking device, one of the first steps is configuring a

unique device name or hostname.

Command syntax check

verifies that a valid command was entered by the user. When a command is entered, the command line interpreter evaluates the command from left to right. If the interpreter understands the command, the requested action is executed, and the CLI returns to the appropriate prompt. However, if the interpreter cannot understand the command being entered, it will provide feedback describing what is wrong with the command.

to enter line sub-configuration mode

you use the line command followed by the management line type and number you wish to access.

Some of the differences between various types of media include:

•Distance the media can successfully carry a signal •Environment in which the media is to be installed •Amount of data and the speed at which it must be transmitted •Cost of the media and installation

To move from user EXEC mode to privileged EXEC mode, use the

enable

Interface Configuration Mode

Used to configure a switch port or router network interface.

default name for a Cisco IOS switch is

"Switch."

Global configuration mode is identified by a prompt that ends with

(config)# after the device name

hostnames should

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

user interacts using

text based program

An IPv4 subnet mask is a

32-bit value that separates the network portion of the address from the host portion

I DO NOT CLAIM THAT THIS IS A COMPLETE LIST OF ALL DISCUSSED TOPICS.

IF YOU DON'T KNOW SOMETHING, NOT MY FAULT.

To access the switch remotely, an

IP address and a subnet mask must be configured on the SVI

There are a number of excellent terminal emulation programs available for connecting to a networking device either by a serial connection over a console port or by a SSH/Telnet connection. Some of these include:

PuTTY Tera Term SecureCRT OS X Terminal These programs allow you to enhance your productivity by adjusting window sizes, changing font sizes, and changing color schemes.

default prompt for interface configuration mode is

Switch(config-if)#.

the default prompt for line configuration mode is

Switch(config-line)#

Console

This is a physical management port that provides out-of-band access to a Cisco device. Out-of-band access refers to access via a dedicated management channel that is used for device maintenance purposes only.

Keyword

a specific parameter defined in the operating system (in the figure, ip protocols)

To create a banner message of the day on a network device, use the ____ the message of the day # global config command.

banner motd #

CLI

command-line interface

Network communications depend on

end user device interfaces, networking device interfaces, and the cables that connect them.

GUI

graphical user interface