Chapter 2 Intro to Routing & Switching

Upon completion of this chapter you will be able to:  Explain the purpose of Cisco IOS.      Explain how to access and navigate Cisco IOS to configure network devices.

Describe the command structure of 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.

2.1.1

 Cisco Internetwork Operating System (IOS)  On all Cisco devices  Stored on flash/flash memory card    Non-volatile Stays w/out power Can be overwritten & upgraded  When powered, copied from flash & runs in RAM

 Take a look at the router  How do you think we can access the IOS?

2.1.2

 Out-of-band management  Means direct maintenance access only  Can access when nothing is configured yet  Need a computer w/ terminal emulation software & console cable  Assign a password to it!

 Telnet    Remote access Plain-text password One active interface must be configured  Secure Shell (SSH)  Remote access w/ encryption  Aux Port    Out-of-band connection/maintenance Uses telephone line Can be used like console port

 What does IOS stand for?

 Internetwork Operating System  Where is the IOS stored on a Cisco router & switch?

 In flash memory  When a router or switch boots up, it loads the IOS from where to where?

 Flash to RAM  What port will you most likely connect to for 1 st time config & direct maintenance?

 Console

2.1.3

 Router> enable (en)  Router# configure terminal (config t)  Router (config)# interface xxx (int)  Router (config-if)#  Router (config-line)#exit (goes back one mode)  Ctrl+Z or end= takes back to privileged  Switch# disable (goes back to user)

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

 Provide info only  Different commands in different modes 

show startup-config (show start)

 Displays the saved configuration located in NVRAM.



show running-config (show run)

 Displays the contents of the currently running configuration file.

 2.1.4.8

  Navigating the IOS Packet Tracer  2.1.4.9

 Establishing a Console Session with Tera Term

 What are the settings in a terminal emulation program to access the CLI?

2.2.1

 Create a two PC network connected via a switch  Setting a name for the switch  Limiting access to the device configuration  Configuring banner messages  Saving the configuration

 What are the default hostnames?

 Must be in privileged mode

 Secure location  Set passwords



We’ll use cisco & class

 Use passwords that are more than 8 characters  Use combination of upper & lowercase letters, numbers, special characters  Avoid using the same password for all devices  Avoid using common words such as password or administrator END OF DAY 3

 In Packet Tracer, complete:       Privileged enable password (cisco) Privileged enable secret password (class) Console password (cisco) VTY password (cisco) Banner MOTD Encrypt all passwords  Then verify all passwords are encrypted by show run END OF DAY 3

2.2.3

 2.2.3.3

 Configuring a Switch  You will perform basic switch configurations.

  You will secure access to the command-line interface (CLI) and console ports using encrypted and plain text passwords. You will also learn how to configure messages for users logging into the switch. These banners are also used to warn unauthorized users that access is prohibited.

 What mode do you need to be in to make configuration changes?  If you erase the startup-config, what else will you need to do in order to return the device to factory default?

2.3

 All end devices have an IP address  IPv4- 192.168.10.25 255.255.255.0

   4 octets 0-255 in each Subnet mask is included with it

 Virtual interface  Allows remote access

 2.3.2.5

 You will first perform basic switch configurations.   Then you will implement basic connectivity by configuring IP addressing on switches and PCs.

When the IP addressing configuration is complete, you will use various show commands to verify configurations and use the ping command to verify basic connectivity between devices.

 Ping  Remote device or device you connect to  PC to switch  PC to PC  127.0.0.1 tests TCP/IP on you

 Build & configure a small network in Packet Tracer  Configure a switch & test it END OF DAY 4

 Complete the study guide handout  Take the quiz on netacad.com

 Jeopardy review

In this chapter, you learned:  Services provided by the Cisco IOS accessed using a CLI • • • Accessed by the console port, the AUX port, or through telnet or SSH Can make configuration changes to Cisco IOS devices A network technician must navigate through various hierarchical modes of the IOS  Cisco IOS routers & switches use a similar IOS

 Introduced the initial settings of a Cisco IOS switch device • • • • Setting a name Limiting access to the device configuration Configuring banner messages Saving the configuration

Chapter 2 Intro to Routing & Switching