The document outlines various operational modes of a router, including user execution mode, privilege mode, and global configuration mode, with details on their functions and commands. It provides specific instructions on how to configure settings such as IP addresses, passwords, and routing protocols, as well as troubleshooting tips. Additionally, it discusses the significance of the router's register values and methods for breaking router passwords.

1. Basic Modes of router
• User Execution Mode. (Default mode) Router>
• Privilege Execution or Administrative Mode. Router#
• Global Configuration Mode. Router (Config)#
Sub-Modes Of Router
• Interface Configuration Mode. Router (Config-if)#
• Line Configuration Mode. Router (Config-Line)#
• Router Configuration Mode. Router (Config-Router)#
Rom Monitor Mode / Trouble Shooting Mode
• ROMMON> or >

2. USER EXECUTIVE MODE
• USER MODE
• Router> is the user mode, i,e the default prompt. It
means that when ever a router boots successfully it lands
into the user mode. Router cannot be configured from this
mode, but it is used for just monitoring purpose.
• We can not see, save and change the configuration of
router.
• We can run some cmds such as ping, telnet etc.

3. Privilege mode
• PRIVILEGE MODE
It is the administrative mode, we can check whether the
settings and configurations made have been implemented
or not. If it is new router all the interfaces are by default
shut down.
• It is used to see and save the configuration of router.
• We can set clock ,ping,Telnet,Save,show, history size etc.
• Router>enable
Password: 1.Enable password (Simple)
2.Enable secret (Encrypted)
• Router#

4. Global Configuration Mode
As the name indicates, it is a global configuration mode i,e.
we can configure any interface from this mode, just by
entering into the interface mode.
We can change every configuration of router such as ip
address or password etc.
Router # Configure terminal
Router(config)#
Exit = Set back one-by-one mode
Ctrl+Z = Set back to Privilege Mode
Ctrl+P = Show previous commands

5. Interface Configuration Mode
• In this mode, we can set ip address over any interface such as ethernet,
serial, BRI, AUI etc.
• Router (config)# Interface e 0 , e0/0 ,f0/0
• Router (config)# Interface s 0 , s0/0 , s0/0/0
• Router (config)# Interface bri 0 , bri0/0
• Router(config-if)#
Line Configuration Mode
In this mode , we can set password over any line such as console line , aux
line and vty line etc.
Router (config)# line console 0
Router (config)# line aux 0
Router (config)# line vty 0 4 ( 5 telnet sessions can run at a time)
Router(config-line)#

6. Router Configuration mode:-
• Router (config)# router <Routing Protocol>
• Router (config-Router)#
RIP : Routing information protocol
RIPV2 : Routing information protocol version 2
IGRP : Interior gateway routing protocol
EIGRP : Enhanced IGRP
OSPF : Open shortest path first
IS-IS : Intermediate system-Intermediate system
BGP : Border gateway protocol

7. Troubleshooting/ Rom Monitor :-
• ROMMON1>
or
>
Power ON router and press Ctrl+Break
you can enter rom monitor mode

8. How we can set Line/Login password ?
• Router(config)# Line console 0
• Router(config-line)# Password 1234
• Router(config-line)# Login
• Router(config-line)# end
• Router# Show running-config
• Rouuter# sh run
(This command is used to show the running
configuration.)
Router# Copy Running-config Startup-config
Router # Write (Those 2 commands are used for
save the configuration )

9. How to set Enable password ?
• Router (config)# Enable password 123
• Router (config)# No Enable password
How to set Enable Secret ?
Router (config)# Enable Secret 111
Router (config)# No Enable Secret

10. How to Encrypt all passwords ?
• Router(config)#Service password-Encrytion
• Router(config)# No Service password-encrypt
How to configure Banner ?
Router(config)# banner motd #
Enter text ……….with end character #
#Welcome gud morning#
Router(config)#exit
Router#exit
How to Change Host name ?
Router(config)# Hostname Cisco
Cisco(config)# exit
Cisco#

11. How to Assign IP address ?
• Router(config)# interface f0/0
• Router(config-if)# ip address 10.0.0.1 255.0.0.0
• Router(config-if)# no shutdown
• Router(config-if)# exit
• Router(config)# exit
• Router# Ping 10.0.0.1
!!!!!!!!! Success rate 100%
Router# ping 10.0.0.2
……..Success rate is 0 %
Router# show running-config
Router# show interfaces
Ruoter# show interfaces f0/0
Ruoter# show ip interface brief
f0/0
10.0.0.1/8
PC
10.0.0.2/8
10.0.0.1 DG

12. Show Command messages
• Interface is up, Line protocol is up
• Interface is up, line protocol is Down
• Interface is down, Line protocol is Down
• Interface is Administratively down

13. Configure Telnet (PC-Router)
• Telnet : It is a service i.e. used to connect remote pc
with local pc in text mode for this service we use a
protocol i.e. TCP(Transmission control Protocol).It is
an authenticated service.
• 1. Configure Router Ethernet interface and pc with
same network ip address
Router(config)#interface f0/0
Router(config-if)#ip address 10.0.0.1 255.0.0.0
Router(config-if)#no shutdown

14. • 2. Configure Enable password or Enable Secret .
Router(config)# Enable password 1234
3. Configure VTY line Password
Router(config)# line vty 0 4
Router(config-line)# Password 12345
Router(config-line)# login
Router(config-line)# end
Router#
4. Goto Pc command prompt
C:>Ping 10.0.0.1
Reply From 10.0.0.1
C:>Telnet 10.0.0.1
Password: <vty password>
Router> Enable
Password: <Enable/enable secret>
Router#
f0/0
10.0.0.1/8
PC
10.0.0.2/8
10.0.0.1 DG

15. What is REGISTER ?
• Router # Show version (Use to Show the register value)
• It is 16 bit hexa-decimal value stored in NVRAM i.e.
Used to set the boot sequence
• Register Description
0x2102 Router boot from Flash(Default value)
0x2101 Router Boot from ROM
0x2100 Router don’t boot but directly enter
Into Rom monitor mode.
0x2142 Router boot from 0x2102, but don’t startup
configuration (Bypass NVRAM)
0x2141 Router boot from 0x2101, but don’t startup
configuration

16. How we can Break Router Password ?
• Boot Router with rom monitor mode .Power ON router and press
(CTRL+Break)
ROMMON1> Confreg 0x2142 >o/r 0x2142
ROMMON1> Reset >I
i=reset
After reboot router it shows a message i.e.
Would you like to enter initial configuration dialog (yes/no): N
Press Return to get Started
Router> Enable
Router# Configure Terminal
Router (config)# Config-register 0x2102
Router (config)# exit
Router# write