Cisco Networking/CCENT/IOS Basics

This lesson covers basic router and switch configuration using IOS commands.

Objectives and Skills
Objectives and skills for the IOS basics portion of Cisco CCENT certification include:
 * Configure and verify utilizing the CLI to set basic Router configuration
 * Hostname
 * banner
 * motd
 * Local user & password
 * Enable secret password
 * Console logins
 * exec-timeout
 * service password encryption
 * copy run start

Readings

 * 1)  Cisco IOS
 * 2) Cisco: IOS and Configuration Basics
 * 3) Cisco: Using the Command-Line Interface in Cisco IOS Software
 * 4) Cisco: Telnet, Console and AUX Port Passwords on Cisco Routers Configuration Example

Multimedia

 * 1) YouTube: Cisco IOS CLI for Beginners - Part 1
 * 2) YouTube: Cisco IOS CLI for Beginners - Part 2
 * 3) YouTube: Cisco IOS CLI for Beginners - Part 3
 * 4) YouTube: Cisco IOS CLI for Beginners - Part 4
 * 5) YouTube: Cisco Router IOS - Command Line basics

enable
To enter privileged EXEC mode, or any other security level set by a system administrator, use the enable EXEC command. enable

disable
To exit privileged EXEC mode and return to user EXEC mode, or to exit to a lower privilege level, enter the disable EXEC command. disable

configure terminal
To enter global configuration mode, use the configure terminal command in privileged EXEC mode. configure terminal

exit
To exit any configuration mode to the next highest mode in the CLI mode hierarchy, use the exit command in any configuration mode. To close an active terminal session by logging off the router, use the exit command in EXEC mode. exit

hostname
To specify or modify the hostname for the network server, use the hostname command in global configuration mode. hostname

ip domain-name
To configure the domain name server (DNS) domain name, use the ip domain-name command in global configuration mode. ip domain-name 

banner login
To define and enable a customized banner to be displayed before the username and password login prompts, use the banner login global configuration command. banner login # #

banner motd
To define and enable a message-of-the-day (MOTD) banner, use the banner motd global configuration command. banner motd # #

Command Sequence
A global configuration command sequence to enable privileged EXEC mode, enter global configuration mode, specify a hostname and banner messages, exit global configuration mode, disable privileged EXEC mode, and log off the router is: enable configure terminal hostname router ip domain-name example.com banner login #Authorized users only!# banner motd #System maintenance will occur on Friday!# exit disable exit

line
To identify a specific line for configuration and enter line configuration collection mode, use the line command in global configuration mode. line console 0

password
To specify a password on a line, use the password command in line configuration mode. password

login
To enable password checking at login, use the login command in line configuration mode. login

username
To establish a username-based authentication system, use the username command in global configuration mode. username password

login local
To enable username and password checking at login, use the login local command in line configuration mode. login local

exec-timeout
To set the interval that the EXEC command interpreter waits until user input is detected, use the exec-timeout line configuration command. exec-timeout

enable password
To set a local clear-text password to control access to various privilege levels, use the enable password command in global configuration mode. enable password

enable secret
To specify an additional layer of security over the enable password command, use the enable secret command in global configuration mode. enable secret

service password-encryption
To encrypt passwords, use the service password-encryption command in global configuration mode. service password-encryption

Command Sequence
A command sequence to configure passwords might be similar to the following. enable configure terminal

line console 0 password letmein login exit

enable secret cisco service password-encryption exit

show running-config exit

A command sequence to configure usernames and passwords might be similar to the following. enable configure terminal

username admin1 password secret1 username admin2 password secret2

line console 0 login local exit

enable secret cisco service password-encryption exit

show running-config exit

show running-config
To display the contents of the current running configuration file or the configuration for a specific module, Layer 2 VLAN, class map, interface, map class, policy map, or virtual circuit (VC) class, use the show running-config command in privileged EXEC mode. show running-config show run

show startup-config
The show startup-config command displays the startup configuration file contained in NVRAM or specified by the CONFIG_FILE environment variable. show startup-config show start

copy
To copy any file from a source to a destination, use the copy command in privileged EXEC or diagnostic mode. copy
 * 1) Configure a router hostname, banner login, and banner motd messages.Cisco CCENT Router.png
 * 2) Add a router to a new GNS3 project and start the device.
 * 3) Open the console for the router and practice using the following commands.
 * 4)  Exit the router console session and open the console again to test the configuration.
 * 5) Configure router console password security.Cisco CCENT Router.png
 * 6) Add a router to a new GNS3 project and start the device.
 * 7) Open the console for the router and practice using the following commands.
 * 8) Verify the configuration using the following command.
 * 9) Exit the router console session and open the console again to test the configuration.
 * 10) Configure router console username and password security.Cisco CCENT Router.png
 * 11) Add a router to a new GNS3 project and start the device.
 * 12) Open the console for the router and practice using the following commands.
 * 13) Verify the configuration using the following command.
 * 14) Exit the router console session and open the console again to test the configuration.
 * 15) Manage router configuration.Cisco CCENT Router.png
 * 16) Use one or more of the router configurations above and manage the configuration using the following commands.
 * 17) After restarting the router, verify the configuration using the following command.
 * 18) Clear the router configuration using the following commands.
 * 19) After restarting the router, verify the configuration using the following command.
 * 1) Verify the configuration using the following command.
 * 2) Exit the router console session and open the console again to test the configuration.
 * 3) Configure router console username and password security.Cisco CCENT Router.png
 * 4) Add a router to a new GNS3 project and start the device.
 * 5) Open the console for the router and practice using the following commands.
 * 6) Verify the configuration using the following command.
 * 7) Exit the router console session and open the console again to test the configuration.
 * 8) Manage router configuration.Cisco CCENT Router.png
 * 9) Use one or more of the router configurations above and manage the configuration using the following commands.
 * 10) After restarting the router, verify the configuration using the following command.
 * 11) Clear the router configuration using the following commands.
 * 12) After restarting the router, verify the configuration using the following command.
 * 1) Configure router console username and password security.Cisco CCENT Router.png
 * 2) Add a router to a new GNS3 project and start the device.
 * 3) Open the console for the router and practice using the following commands.
 * 4) Verify the configuration using the following command.
 * 5) Exit the router console session and open the console again to test the configuration.
 * 6) Manage router configuration.Cisco CCENT Router.png
 * 7) Use one or more of the router configurations above and manage the configuration using the following commands.
 * 8) After restarting the router, verify the configuration using the following command.
 * 9) Clear the router configuration using the following commands.
 * 10) After restarting the router, verify the configuration using the following command.
 * 1) Verify the configuration using the following command.
 * 2) Exit the router console session and open the console again to test the configuration.
 * 3) Manage router configuration.Cisco CCENT Router.png
 * 4) Use one or more of the router configurations above and manage the configuration using the following commands.
 * 5) After restarting the router, verify the configuration using the following command.
 * 6) Clear the router configuration using the following commands.
 * 7) After restarting the router, verify the configuration using the following command.
 * 1) After restarting the router, verify the configuration using the following command.
 * 2) Clear the router configuration using the following commands.
 * 3) After restarting the router, verify the configuration using the following command.
 * 1) After restarting the router, verify the configuration using the following command.
 * 2) Clear the router configuration using the following commands.
 * 3) After restarting the router, verify the configuration using the following command.
 * 1) Clear the router configuration using the following commands.
 * 2) After restarting the router, verify the configuration using the following command.
 * 1) After restarting the router, verify the configuration using the following command.
 * 1) After restarting the router, verify the configuration using the following command.
 * 1) After restarting the router, verify the configuration using the following command.

Lesson Summary

 * Cisco IOS (originally Internetwork Operating System) is software used on most Cisco Systems routers and network switches.
 * IOS is a package of routing, switching, internetworking and telecommunications functions integrated into a multitasking operating system.
 * Cisco IOS command modes determine the commands and privilege level of the current user.
 * User EXEC mode allows connection to remote devices, changing terminal settings on a temporary basis, performing basic tests, and listing system information. User EXEC mode is indicated by a   prompt.
 * Privileged EXEC mode allows all EXEC commands available on the system. Privileged EXEC mode is indicated by a   prompt.
 * Global Configuration mode commands allow configuration of the system as a whole, and access to specific configuration modes and submodes. Global Configuration mode is indicated by a   prompt.
 * ROM Monitor mode is used for system diagnostics or when a valid system image is not found. ROM Monitor mode is indicated by a   prompt.
 * Setup mode is an interactive sequence that allows first-time configuration of devices.
 * More than 100 detail configuration modes and submodes are available for different interfaces and protocols.
 * Almost every configuration command also has a  form used to disable the feature or function.
 * Context-sensitive help is available by entering  in any command mode.
 * To enter privileged EXEC mode, or any other security level set by a system administrator, use the  EXEC command.
 * To exit privileged EXEC mode and return to user EXEC mode, or to exit to a lower privilege level, enter the  EXEC command.
 * To enter global configuration mode, use the  command in privileged EXEC mode.
 * To exit any configuration mode to the next highest mode in the CLI mode hierarchy, use the  command in any configuration mode.
 * To close an active terminal session by logging off the router, use the  command in EXEC mode.
 * To specify or modify the hostname for the network server, use the  command in global configuration mode.
 * To configure the domain name server (DNS) domain name, use the  command in global configuration mode.
 * To define and enable a customized banner to be displayed before the username and password login prompts, use the  global configuration command.
 * To define and enable a message-of-the-day (MOTD) banner, use the  global configuration command.
 * To identify a specific line for configuration and enter line configuration collection mode, use the  command in global configuration mode.
 * To specify a password on a line, use the  command in line configuration mode.
 * To enable password checking at login, use the  command in line configuration mode.
 * To establish a username-based authentication system, use the  command in global configuration mode.
 * To enable username and password checking at login, use the  command in line configuration mode.
 * To set the interval that the EXEC command interpreter waits until user input is detected, use the  line configuration command.
 * To set a local clear-text password to control access to various privilege levels, use the  command in global configuration mode.
 * To specify an additional layer of security over the enable password command, use the  command in global configuration mode.
 * To encrypt passwords, use the  command in global configuration mode.
 * To display the contents of the current running configuration file or the configuration for a specific module, Layer 2 VLAN, class map, interface, map class, policy map, or virtual circuit (VC) class, use the  command in privileged EXEC mode.
 * The  command displays the startup configuration file contained in NVRAM or specified by the CONFIG_FILE environment variable.
 * To copy any file from a source to a destination, use the  command in privileged EXEC or diagnostic mode.
 * To erase a file system or all files available on a file system, use the  command in privileged EXEC or diagnostic mode.
 * To reload the operating system, use the  command in privileged EXEC or diagnostic mode.

Key Terms

 * command-line interface (CLI)
 * A means of interacting with a computer program where the user issues commands to the program in the form of successive lines of text.


 * configuration mode
 * Allows commands that apply to the system as a whole, accessed using the  command.


 * console
 * The text entry and display interface for system administration messages.


 * enable mode
 * Privileged EXEC mode, accessed using the  command.


 * host name
 * A label assigned to a device connected to a computer network and used to identify the device in various forms of electronic communication.


 * IOS image
 * A Cisco system software file used to run Cisco routers and switches.


 * local username
 * Usernames and passwords stored on the local device using the  and   commands.


 * running config file
 * The current system configuration, stored in RAM.


 * startup config file
 * The current system boot configuration, stored in NVRAM.


 * user mode
 * User EXEC mode, accessed by logging into a device.

Assessments

 * Flashcards: Quizlet: CCENT - IOS Basics
 * Quiz: Quizlet: CCENT - Lab Setup