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
1st 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

Displays the saved configuration located in
NVRAM.
 show

startup-config (show start)
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
 Setting
a name for the switch
switch
 Limiting
access to the device configuration
 Configuring
 Saving
banner messages
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
 Take
the study guide handout
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