Router configuration

You are most welcome to this post.

Really thanks to you for your interest in this topics. :)

Hello all !! Hope that you are all well by the grace of almighty. Also you are enjoying computer networking. Me also enjoying computer networking very much. So lets see what we’ll learn from todays post.

Router configuration

Today we’ll learn something about the cisco router and its configuration. We’ll see some basic command of router. We’ll do these simulation using a very powerful network simulator named cisco packet tracer. It is recommended to use latest version of cisco packet tracer. So lets see these.
As we are doing the network simulation in cisco packet tracer, so here we’ll use cisco router. As you know, for a powerful communication router is necessary. Router has an operating system, in the case of cisco router, it is called cisco IOS. You can also call it as “Internetwork operating System for Cisco networking devices ”. So this IOS must have some features like:
 Security
 Addressing
 Routing
 Interfaces
 QoS
 Managing Resources

The IOS operation vary in different network devices. The IOS services are done in a router by using CLI mode. Also the ISO is stored in the flash memory of the router. This flash memory is not a permanent flash memory, but it is a semi permanent flash memory. It provides non volatile storage. So we can say that the contents of flash memory can’t damage, when it loses power.
Now come to the ports of a cisco router. The cisco router has some types of ports, including:
 Fast Ethernet port
 Auxiliary port
 Telnet access port
 Modem access port
 Console port
 Terminal access port
 Serial port
Also you may find other types of ports. Now come to the cisco IOS commands. You need to use the cisco IOS command by using CLI mode. You can go to the CLI mode of a router, by using a console cable through a PC. But before going to CLI for using command you need to have some concept about the command modes. There are mainly two primary command modes. One is User EXEC mode and the other is Privileged EXEC mode. Also there are two types of modes you need to remember. They are global configuration mode and Other configuration mode. SO lets see the image about the Command modes.
Some very important commands are the “show ” command of router. With the help of this command you can now be able to see the configuration and process of routers. It is very helpful in the case of network monitor. Some show commands are:
Show version
Show flash
Show interface
Show process CPU
Show protocols
Show memory
Show stacks
Show running-config
Show startup-config
When you’ll enter the CLI mode of a router, then you will be in the user EXEC mode.
R2-Central>?
Exec commands:
<1-99> Session number to resume
connect Open a terminal connection
disable Turn off privileged commands
disconnect Disconnect an existing network connection
enable Turn on privileged commands
exit Exit from the EXEC
logout Exit from the EXEC
ping Send echo messages
resume Resume an active network connection
show Show running system information
ssh Open a secure shell client connection
telnet Open a telnet connection
terminal Set terminal line parameters
traceroute Trace route to destination
So from the list you can see that, by writing enable command you can enter the Privilrgrd EXEC mode. Also you can show the specific port working process and assigned IP address of that specific port.
For example: show ip interface command will show you the interface details of the router.
There are so many show commands, you can see them by typing the specific word, after the show:
aaa Show AAA values
access-lists List access lists
arp Arp table
cdp CDP information
class-map Show QoS Class Map
clock Display the system clock
controllers Interface controllers status
crypto Encryption module
debugging State of each debugging option
dhcp Dynamic Host Configuration Protocol status
dot11 IEEE 802.11 show information
file Show filesystem information
flash: display information about flash: file system
flow Flow information
frame-relay Frame-Relay information
history Display the session command history
hosts IP domain-name, lookup style, nameservers, and host table
interfaces Interface status and configuration
ip IP information
line TTY line information
lldp LLDP information
logging Show the contents of logging buffers
login Display Secure Login Configurations and State
mac-address-table MAC forwarding table
ntp Network time protocol
parser Show parser commands
policy-map Show QoS Policy Map
privilege Show current privilege level
processes Active process statistics
protocols Active network routing protocols
queue Show queue contents
queueing Show queueing configuration
running-config Current operating configuration
secure Show secure image and configuration archive
sessions Information about Telnet connections
snmp snmp statistics
spanning-tree Spanning tree topology
ssh Status of SSH server connections
standby standby configuration
startup-config Contents of startup configuration
storm-control Show storm control configuration
tcp Status of TCP connections
tech-support Show system information for Tech-Support
terminal Display terminal configuration parameters
users Display information about terminal lines
version System hardware and software status
vlan-switch VTP VLAN status
vtp Configure VLAN database
So these are the show commands.
If you want to work in switch, you can also type these commands, but all the commands may not work for switch.

If you have a look at the screenshots, then it also may be helpful for you.

If you want, you can also enjoy this video about the router configuration: