Transcript Semester 2 Chapter 5 & 6 - Institute of Technology Sligo

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Router Startup and Setup
& Router Configuration 1
Semester 2
Chapter 5/6
Paul Flynn
Institute of Technology Sligo - Dept of Computing
Table of Contents
Boot Sequence and Setup Mode
System Configuration Dialog
Router Configuration Files
Router Configuration Modes
Configuration Methods
Challenge Labs
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Router Boot Sequence and
Setup
Mode
 Router Startup Routine


Router Startup
Sequence
Related Commands
Table of Contents
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Router Startup Routine

When a Cisco router powers up, it performs a
power-on self test (POST).
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Executes diagnostics from ROM on all hardware
Verifies the basic operation of the CPU, memory, and
network interface ports
Proceeds with software initialization
A router initializes by loading the bootstrap, the
IOS, and a configuration file.
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If the router cannot find a configuration file, then it
enters setup mode
NVRAM stores a backup copy of the new
configuration from setup mode
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Router Startup Routine

The goal of the startup routines for Cisco IOS
software is to start the router operations. The
router must deliver reliable performance in its
job of connecting the user networks it was
configured to serve. To do this, the startup
routines must:
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Make sure that the router comes up with all its
hardware tested.
Find and load the Cisco IOS software that the router
uses for its operating system.
Find and apply the configuration statements about the
router, including protocol functions and interface
addresses.
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Router Startup Sequence

After the power-on self test on the router, the following
events occur as the router initializes:
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Step 1 - The generic bootstrap loader, in ROM, executes on the CPU
card. A bootstrap is a simple, preset operation to load instructions that in
turn cause other instructions to be loaded into memory, or cause entry
into other configuration modes.
Step 2 - The operating system (Cisco IOS) can be found in one of
several places. The location is disclosed in the boot field of the
configuration register. If the boot field indicates a Flash, or network load,
boot system commands in the configuration file indicate the exact
location of the image.
Step 3 - The operating system image is loaded. Then, when it is loaded
and operational, the operating system locates the hardware and
software components and lists the results on the console terminal.
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Router Startup Sequence
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Step 4 -- The configuration file saved in NVRAM is loaded into
main memory and executed one line at a time. These
configuration commands start routing processes, supply
addresses for interfaces, set media characteristics, and so on.
Step 5 -- If no valid configuration file exists in NVRAM, the
operating system executes a question-driven initial configuration
routine referred to as the system configuration dialog, also called
the setup dialog.
Setup is not intended for entering complex
protocol features in the router. It is used to bring
up a minimal configuration.
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Router Startup Sequence
Know the sequence!
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Related Commands
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show startup-config (show config on Cisco IOS 10.3
or earlier) – display the backup configuration file.
show running-config (write term on Cisco IOS 10.3 or
earlier) – display the active configuration file.
erase startup-config (write erase on Cisco IOS 10.3 or
earlier) – deletes the backup configuration file in
NVRAM.
reload (reboot) command reloads the router, causing it
to run through the entire startup process.
setup is used to enter setup mode from the privileged
EXEC prompt
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System Configuration
Dialog
 The setup Command
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Setting up global and
interface parameters
Setting up script review
and use
Setup Lab Challenge
Table of Contents
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The setup Command
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The main purpose of the setup mode is to bring
up, quickly, a minimal configuration for any
router that cannot find its configuration from
another source.
Default answers appear in square brackets [ ]
following the question. Press the Return key to
use these defaults.
During the setup process, you can press
Control+C at any time to terminate the process
and start over.
Once setup is terminated, all interfaces will be
administratively shutdown.
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

The
Command
When
yousetup
completed,
the screen will
display the configuration that you have just
created.
You will then be asked whether you want to
use this configuration.
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If you enter "yes", the configuration will be
executed and saved to NVRAM.
If you answer "no", the configuration will not be
saved and the process will begin again.
If a --More-- prompt appears, press the
space bar to continue..
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Setting Global Parameters
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After viewing the current interface summary, a prompt
will appear on your monitor, indicating that you are to
enter the global parameters for your router.
Configuring global parameters appears on your
monitor. It indicates that you are to enter the global
parameters that you set for your router.
The first global parameter allows you to set the router
host name.
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This host name will be part of the Cisco IOS prompts for all
configuration modes.
At initial configuration, the default router name is [Router].
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Setting Global Parameters
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The next global parameters allows you to set the various passwords
used on the router.
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You must enter an enable password.
When you enter a string of password characters for the prompt, "Enter
enable secret"; the characters are processed by Cisco proprietary
encryption.
This enhances the security of the password string.
Whenever anyone lists the contents of the router configuration file, this
enable password appears as a meaningless string of characters.
Setup recommends, but does not require, that the "enable
password" be different from the "enable secret word".
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Setting Global Parameters

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The "enable secret word" is a one-way
cryptographic secret word that is used instead of
the "enable password" when it exists. The
"enable password" is used when no "enable
secret word" exists. It is also used when using
older versions of the IOS.
All passwords are case sensitive and can be
alphanumeric.
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Setting Global Parameters
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When you are prompted for parameters for
each installed interface, use the
configuration values that you have
selected for your router.
Whenever you answer yes to a prompt,
additional questions may appear regarding
the protocol.
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Interface Parameters
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When you are prompted for parameters for
each installed interface, you need to use
the configuration values you have
determined for your interface to enter the
interface parameters at the prompts
In order to fully understand setup mode
complete the Lab

Lab 5.2.3 Router setup command
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Script Review and Use


When you complete the configuration process for all
installed interfaces on your router, the setup command
program will display the configurations that you have
created.
The setup process will then ask if you want to use this
configuration.
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If you answer yes, the configuration will be executed and saved
to NVRAM.
If you answer no, the configuration will not be saved, and the
process will begin again.
There is no default for this prompt; you must answer either yes
or no.
After you have answered yes to the last question, your system
will be ready to use.
If you want to modify the configuration you have just established,
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Script Review and Use
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The script tells you to use the configuration
mode to change any commands after setup has
been used.
The script file generated by setup is additive;
you can turn features on with setup, but you
cannot turn them off.
Also, setup does not support many of the
advanced features of the router, or features that
require a more complex configuration.
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Challenge Lab

Your Skills Assessment will be based on
this Lab, make sure you have completed
it…

Lab 5.3.1 Router setup challenge
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Summary
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The router initializes by loading a
bootstrap, the operating system, and a
configuration file.
If the router cannot find a configuration file,
the router enters setup mode.
The router stores a backup copy of the
new configuration from setup mode in
NVRAM.
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Router Configuration Files
Table of Contents
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Configuration File Info
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Configuration files can come from the console, NVRAM,
or a TFTP server.
A router uses information from the configuration file
when it starts up:
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Cisco IOS software version
Router identification
Boot file locations
Protocol information
Interface configurations
The configuration file contains commands to customize
router operation.
If there is no configuration file available, the system
configuration dialog setup guides you through the
process of creating one
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Release 11.x Config-Files

Router configuration can be done in several
ways. You can use
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the privileged EXEC configure command to
configure from a virtual (remote) terminal,
a modem connection, or
a console terminal.
You can enter changes to an existing
configuration at any time.
You can use the privileged EXEC configure
command to load a configuration from a network
TFTP server, which allows you to maintain and
store configuration information at a central site.
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Release 11.x Config-Files
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Some configuration commands include:
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configure terminal – configures manually from the console
terminal
configure memory – loads configuration information from
NVRAM
copy tftp running-config – loads configuration information from
a network TFTP server into RAM
show running-config – displays the current configuration in
RAM
copy running-config startup-config – stores the current
configuration from RAM into NVRAM
copy running-config tftp – stores the current configuration from
RAM on a network TFTP server
show startup-config – displays the saved configuration, which
is the contents of NVRAM
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Lab

To fully understand Router configuration, do the
lab.

Lab 6.1.2 Router config HyperTerminal
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Pre-Release 11.0 config-files
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The commands used with Cisco IOS, Release
10.3 and earlier, have been replaced with new
commands.
The old commands that have been replaced
continue to perform their normal functions in the
current release, but are no longer documented
Support for these commands will cease in a
future release
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Early Commands
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Configuration commands for Release 10.3 and earlier:
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config term – configures manually from the console terminal
config mem – loads configuration information from NVRAM
config net – loads configuration information from a network
TFTP server into RAM
write term – displays the current configuration in RAM
write mem– stores the current configuration from RAM into
NVRAM
write net – stores the current configuration from RAM on a
network TFTP server
show config – displays the saved configuration, which is the
contents of NVRAM
write erase – erases the contents of NVRAM
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Copying to a TFTP Server

To store (backup) the current copy of the
configuration file in RAM on a TFTP server use
the copy running-config tftp command and
complete the following tasks:
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Step 1 – Enter the copy running-config tftp
command.
Step 2 – Enter the IP address of the host that you
want to use to store the configuration file.
Step 3 – Enter the name you want to assign to the
configuration file.
Step 4 – Confirm your choices by answering yes
each time.
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Copying from a TFTP Server

To configure a router by loading the
configuration file stored on one of your network
TFTP servers, complete the following tasks:
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Enter the command copy tftp running-config
At the prompt, select a host or network configuration
file.
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The network configuration file contains commands that apply
to all routers and terminal servers on the network.
The host configuration file contains commands that apply to
one router in particular.
At the next prompt, enter the IP address of the the
TFTP server from which you are retrieving the
configuration file.
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Copying from a TFTP Server

Finally, enter the name of the configuration file or
accept the default name.
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The filename convention is UNIX-based.
The default filename is hostname -confg for the host
file and network -confg for the network configuration
file.
In the DOS environment, the server filenames are
limited to eight characters plus a three-character
extension (e.g., router.cfg).
Confirm the configuration filename and the server
address that the system supplies.
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Lab

Note: You must configure the default
gateway IP address that the TFTP server
is attached to on the Router or the lab will
not work

Lab 6.1.4 Router Configuration TFTP
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NVRAM Commands

These commands manage the contents of
NVRAM with Release 11.x:
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configure memory – Loads configuration information
from NVRAM.
erase startup-config – Erases the contents of
NVRAM.
copy running-config startup-config – Stores the
current configuration from RAM (the running
configuration) into NVRAM (as the startup or backup
configuration).
show startup-config – Displays the saved
configuration, which is the contents of NVRAM.
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NVRAM Commands

These commands manage the contents of
NVRAM with Release 10.3 and earlier:
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configure memory – Loads configuration information
from NVRAM.
write erase – Erases the contents of NVRAM.
write memory – Stores the current configuration from
RAM (the running configuration) into NVRAM (as the
startup or backup configuration).
show configuration – Displays the saved
configuration, which is the contents of NVRAM.
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Router Configuration Modes
Table of Contents
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Using Configuration Modes

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The EXEC mode interprets the commands you type and
carries out the corresponding operations.
You must log into the router before you can enter an
EXEC command.
There are two EXEC modes (user mode and privileged
mode).
The EXEC commands available in user mode are a
subset of the EXEC commands available in privileged
mode.
From privileged mode, you can also access global
configuration mode and specific configuration modes
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Using Configuration Modes
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Some specific configuration modes are:
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Interface
Subinterface
Controller
Map-list
Map-class
Line
Router
IPX-router
Route-map
If you type exit, the router will back out one level, eventually allowing you to
log out. In general, typing exit from one of the specific configuration modes
will return you to global configuration mode.
Pressing Ctrl-Z leaves configuration mode completely and returns the router
to privileged EXEC mode.
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Overview of Router Modes
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Lab

Complete the following lab :


Lab 6.2.1 Basic router configuration
You can also use the “Seven steps to
Router Configuration Heaven” handout:

http://cisco.netacad.net/ccnaDownloads/2/wwi
dulsk_Seven_Steps_to_Router_Configuration
_Heaven.doc
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Global Configuration Modes
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Global configuration commands apply to features that affect the
system as a whole.
Use the privileged EXEC command configure to enter global
configuration mode. When you enter this command, the EXEC
prompts you for the source of the configuration commands.
Specify terminal, NVRAM, or a file stored on a network server as
the source. The default is to type in commands from the terminal
console. Pressing the return key begins this configuration method.
Commands to enable a particular routing or interface function begin
with global configuration commands:
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To configure a routing protocol (indicated by the prompt config-router)
you first enter a global router protocol command type.
To configure an interface (indicated by the prompt config-if) you first
enter the global interface type and number command. After entering
commands in any of these modes, you finish with the command exit.
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Configuring Routing Protocol
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
After a routing protocol is enabled by a
global command, the router configuration
mode prompt Router (config-router)# is
displayed.
Type a question mark (?) to list the routing
protocol configuration sub-commands
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Interface Config Commands
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Because all router interfaces are automatically in
the administratively down mode, many features
are enabled on a per-interface basis.
Interface configuration commands modify the
operation of an Ethernet, a Token Ring, or a
serial port.
In addition, interface subcommands always
follow an interface command because the
interface command defines the interface type
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Configuring a Specific Int
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On serial links, one side must provide a clocking signal, a DCE; the
other side is a DTE.
By default, Cisco routers are DTE devices, but in some cases they
can be used as DCE devices.
If you are using an interface to provide clocking, you must specify a
rate with the clockrate command.
The bandwidth command overrides the default bandwidth that is
displayed in the show interfaces command and is used by some
routing protocols such as IGRP.

On the Cisco 4000 series routers, there are two connections on the
outside of the box for Ethernet interfaces-an attachment unit interface
(AUI) connector and a 10BASE-T connector. The default is AUI, so you
must specify media-type 10BASE-T if you want to use the other
connection
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Lab

You will get a better handle on all this after
completing the Lab

Lab 6.2.5 Router interface config
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Configuration Methods
Table of Contents
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Release 11.x Config Method

The Figure shows a way
you can:
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Enter configuration
statements
Examine the changes you
have made
If necessary, modify or
remove configuration
statements
Save the changes to a
backup in NVRAM that the
router will use when it
starts up
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Pre-11.0 Release Config
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Password Config Methods

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You can secure your system by using passwords to restrict access.
Passwords can be established both on individual lines and in the
privileged EXEC mode.
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line console 0 – establishes a password on the console terminal
line vty 0 4 – establishes password protection on incoming Telnet
sessions
enable password – restricts access to privileged EXEC mode
enable secret password (from the system configuration dialog to set up
global parameters – uses a Cisco proprietary encryption process to alter
the password character string
You can further protect passwords from being displayed by using the
service password-encryption command. This encryption algorithm
does not match the Data Encryption Standard (DES).
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Router Identification Config
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The configuration of network devices determines the network's
behavior. To manage device configurations, you need to list and
compare configuration files on running devices, store configuration
files on network servers for shared access, and perform software
installations and upgrades.
One of your first basic tasks is to name your router. The name of the
router is considered to be the host name and is the name displayed
by the system prompt. If you do not configure a name, the system
default router name will be Router. You can name the router in
global configuration mode.
You can configure a message-of-the-day banner to be displayed on
all connected terminals. This banner will be displayed at login and is
useful for conveying messages that affect all router users (e.g.
impending system shutdowns). To configure this message, use the
banner motd command in the global configuration mode.
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Challenge Labs
Table of Contents
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Configuration Labs

To master router configuration, do the labs.
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Lab 6.4.1 Router configuration challenge
Lab 6.4.2 Cisco configmaker
Lab 6.4.3 Router config. web browser
Active mental participation in answering lab
questions is crucial to do well on the test.
You will also retain the knowledge longer if you
think about what you are doing and why!