Basics to Configure a CISCO Router to Connect to Internet

7/30/2019 Basics to Configure a CISCO Router to Connect to Internet

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Basics to configure a CISCO router toconnect to internet.

Any Cisco router you have around you say Cisco 1000, 1600, 2500, 2600, And 3600 Series Routers. Any cisco

router you have the below configurations will be able to workout. These configurations will help you connect

your LAN onto internet, Provide basic security to your Local Area Network (LAN) so that no other network

connects if not defined in the configs.

I will go straight to what I have around me to have this configuration done successfully.

1. Router: Cisco 1600 series.

2. ISP Addresses: [IP Address: 192.168.23.11 SubMask: 255.255.255.0 Gateway:192.168.23.1].

3. LAN Addresses: [IP Address: 10.100.10.1 SubnetMask: 255.255.255.0]

4. Console Cable.Step 1:

- Connect your router into power and connect your console cable (will need an RJ-45 to DB-25 adapter).

Power up that router without wasting a lot of time.

- Open up your HyperTerminal: Start -> All Programs -> Accessories ->Communications -> HyperTerminal.

- You can name anything your Connection Description mine is ictmagazine and choose 2nd icon.

- Press OK, Then on the next interface choose a COM port your console is connecting to from the router.

Mine was COM3 then press OK.


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- On the next screen restore to defaults Restore Defaults and you should be having something similar to

that below.

Then pressOK. You should be in your router now.

Well I will avoid you all the boring talk and just dive straight into the really thing configuring a router to

internet, so let us go straight tostep 2.

Please note that the names and password have used those are as per on my router. You can use anything you

prefer to make sure your configurations are secure and matching to your standards.

..............Step 2: Configure Basics

Router>en

Router#config t

Router(config)#hostname ICT

ICT(config)#enable password joinict

ICT(config)#enable secret m@g@z1n3

ICT(config)#ip name-server 208.67.222.222

...............Step 3: Configuring the Line console and vty 0 4

ICT(config)#line console 0

ICT(config-line)#password g3t1n

ICT(config-line)#loginICT(config-line)#exit

ICT(config)#line vty 0 4

ICT(config-line)#password b0b0ut

ICT(config-line)#login

ICT(config-line)#exit

................Step 4: setting up the LAN interface

ICT(config)# interface Ethernet1/0

ICT(config-if)# Description ICTMAGAZINE LAN

ICT(config-if)# ip address 10.100.10.1 255.255.255.0

ICT(config-if)# ip nat inside

ICT(config-if)# no shutdown


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ICT(config-if)# exit

....................Step 5: setting up the INTERNET interface (this interface has IP Addresses provided by

Internet provider ISP)

ICT(config)# interface FastEthernet0/0

ICT(config-if)# Description Broadband InternetICT(config-if)# ip address 192.168.23.11 255.255.255.0

ICT(config-if)# ip nat outside

ICT(config-if)# no shutdown

ICT(config-if)# exit

....................Step 6: Configuring NAT and Routing statements.

ICT(config)# ip nat inside source list 1 interface FastEthernet0/0 overload

ICT(config)# ip route 0.0.0.0 0.0.0.0 192.168.23.1

...................Step 7: Configuring the Access-list 1 (This allows the LAN to get connection to theinternet).

ICT(config)#access-list 1 permit 10.100.10.0 0.0.0.255

..................Step 8: Run show commands to confirm your configurations

ICT(config)#show interface ethernet1/0 (verify the LAN IP configuration)

ICT(config)#show interface fastethernet 0/0 (verify External/ISP IP configuration and status)

ICT(config)# Show ip route (show your routing statement if its correct)

ICT(config)# show ip nat translations (This is to confirm if your nat statements are right)

ICT(config)#show access-lists (configured access lists)

.................Step 9: Save your router configurationsICT(config)#wr

The most likely reason why the router has bypassed the startup configuration stored in NVRAM is that theconfiguration register has not been set properly. To change your configuration register so that the router does notignore or skip the startup configuration upon reboot or power cycle, complete these steps:

From the Router# prompt:

1. Typeconfigure terminal, and press ENTER.2. Typeconfig-register0x2102, and press ENTER.3. Type end, and press ENTER.

To verify the configuration register change, type show version at the Router# prompt, and review yourshowversion command output again. Look for the configuration register setting, which must show a new value uponthe next reload. Here is an example:

Router#configure terminalEnter configuration commands, one per line. End with CNTL/Z.Router(config)#config-register 0x2102Router(config)#end

Router#show version

Cisco Internetwork Operating System SoftwareIOS (tm) 2500 Software (C2500-JS-L), Version 12.1(5),
http://www.cisco.com/en/US/docs/ios/12_3t/fun/command/reference/cfrgt_02.html#wp1125025http://www.cisco.com/en/US/docs/ios/12_3t/fun/command/reference/cfrgt_02.html#wp1125025http://www.cisco.com/en/US/docs/ios/12_3t/fun/command/reference/cfrgt_02.html#wp1125025http://www.cisco.com/en/US/docs/ios/12_3t/fun/command/reference/cfrgt_02.html#wp1124455http://www.cisco.com/en/US/docs/ios/12_3t/fun/command/reference/cfrgt_02.html#wp1124455http://www.cisco.com/en/US/docs/ios/12_3t/fun/command/reference/cfrgt_02.html#wp1124455http://www.cisco.com/en/US/docs/ios/12_3t/fun/command/reference/cfrgt_02.html#wp1124455http://www.cisco.com/en/US/docs/ios/12_3t/fun/command/reference/cfrgt_02.html#wp1125025


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RELEASE SOFTWARE (fc1)Copyright (c) 1986-2000 by cisco Systems, Inc.Compiled Wed 25-Oct-00 05:18 by cmongImage text-base: 0x03071DB0, data-base: 0x00001000

ROM: System Bootstrap, Version 5.2(8a), RELEASE SOFTWAREBOOTFLASH: 3000 Bootstrap Software (IGS-RXBOOT), Version10.2(8a),RELEASE SOFTWARE (fc1)

Router uptime is 11 minutesSystem returned to ROM by reloadSystem image file is "flash:c2500-js-l_121-5.bin"

cisco 2500 (68030) processor (revision D) with 16384K/2048K bytesof memory.Processor board ID 03867477, with hardware revision 00000000

Bridging software.X.25 software, Version 3.0.0.SuperLAT software (copyright 1990 by Meridian Technology Corp).TN3270 Emulation software.1 Token Ring/IEEE 802.5 interface(s)2 Serial network interface(s)32K bytes of non-volatile configuration memory.16384K bytes of processor board System flash (Read ONLY)

Configuration register is 0x2142 (will be 0x2102 at next reload)

When the router is reloaded, the new configuration register setting becomes active.

Router#reloadSystem configuration has been modified. Save? [yes/no]: nProceed with reload? [confirm]

Your router now loads with the startup configuration, and the configuration register is set to 0x2102. Yourconfiguration loads properly after the next reload or power cycle.

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Basics to Configure a CISCO Router to Connect to Internet