Home > Articles > Cisco > CCENT

Network+ Cert Guide: Typical Router Setup

Routers are a key element in modern networks of any size. This article walks readers through typical setup and details some of the most important aspects of an industry representing router from Cisco Systems.
Like this article? We recommend

Like this article? We recommend

There is nothing like getting a new Router shipped to your desk. The smell of the packing peanuts and the static resistant wrapping material is enough the make the head swim with excitement. Now in all honesty, that is all very cool, but it does not really compare to the exhilaration of powering it up, connecting the serial cables to your trusty admin machine, and bending it to your will. Okay you get the idea, you just got a new device, and you need to set it up so that it can fit into your networking environment. We are going to discuss typical thing that will or should be done to get routers ready for a wide deployment in your infrastructure. The news here is that routers are somewhat less intuitive that switches, because compared to their Layer 2 counterparts, routers are almost completely NOT plug and play.

To address this dilemma, we are going to gently start an exploration of what it takes to access, configure, and verify a typical router setup.

Start Up

At this point we need to make a number of assumptions based on the method used to “attach” to the router. As such we will use a terminal emulation program like putty or securecrt running on a Microsoft Windows 7 operating system. Of course, there are almost endless combinations of terminal emulators and computers that could be used for this task, but for a single frame of reference we will use Putty and a Windows-based computer to connect to the router.

Once the computer and the emulation program is selected, it will be necessary to connect a serial cable into a serial (COM) port on the PC and the other end into the console port on the router. Start putty, select the Serial connection type, and specify the COM port. Set the speed of the connection to 9600 baud and click Open. For this to work the router must be on. If you do not immediately see a prompt from the router you may need to press the Enter key. In our illustration, the router will be at the Cisco IOS factory default so the prompt will be:

         --- System Configuration Dialog ---

Would you like to enter the initial configuration dialog? [yes/no]:

Type no and press enter. If you say yes, it will put you in the menu interface. By saying no you well receive the following:

Press RETURN to get started!


Now is a great time to introduce the concept of how Cisco IOS is organized. The Command Line Interface (CLI) concept is built around the idea of modes. These modes dictate what command options are available and what configurations can be made. By moving in and out of these different modes and making necessary configurations changes, we will manipulate the routers configuration. The most logical place to start is identifying the modes we will be using.

On initial connection to a router you have entered what is called EXEC mode. This is the first mode under which commands can be issued from the command-line. From this mode you have access to unprivileged commands:

  • ping—Helps in determining issues with the TCP/IP network and assists in resolving them.
  • telnet —A terminal emulation that enables a user to connect to a remote host or device using a telnet client, usually over port 23.
  • show —You can also use some of the show commands to obtain information about the system. If you want to see the list of things what show can be used with use the “?”.

It is necessary to enter privileged mode to actually configure a router. This is accomplished by using the enable command. Privileged mode is normally password protected but this is not the case with factory default settings. When you issue the command enable and provide the password, you will enter privileged mode. What is important here is how the router will assist the user in keeping track of what mode they are in, because the command-line prompt changes each time you enter a different mode. When you switch from unprivileged to privileged mode, the prompt changes from:


This may seem like a lot of discussion regarding just two modes, but the actual fact is that there are many “sub-modes” and this feature is invaluable in determining what mode or context the router is in.

Global Configuration Mode

To configure any feature of the router, you need to enter the global configuration mode this mode is the stepping off point to any other sub-mode or context. The user knows that they are in global configuration mode based on the prompt:

Router#conf t
Enter configuration commands, one per line.  End with CNTL/Z.

In global configuration mode it is possible to set system-wide or global configuration. One of the most common commands used in this mode is to assign the router a hostname:

Router(config)#hostname NETWORK-plus

This demonstrates that when the hostname is changed we can see the name Router is replaced with what was configured with the hostname command. Another command most commonly used in global configuration mode is the enable secret command:

NETWORK-plus(config)#enable secret routerpassword

Note that the “end” command takes the router back to the privileged exec mode, bypassing global configuration.

Interface Configuration Mode

To apply any configuration to an interface it is necessary to be in configuration for that interface. This means that a router will have a sub-mode level for each interface that it has. In this instance you will configure interface FastEthernet0/0 with an IP address, and bring the interface into service:

NETWORK-plus#conf t
Enter configuration commands, one per line.  End with CNTL/Z.
NETWORK-plus(config)#interface FastEthernet0/0
NETWORK-plus(config-if)#ip address
NETWORK-plus(config-if)#no shut

Using this series of commands, you navigate from privilege exec to global configuration, to the configure interface (config-if) context or sub-mode. Once there you will apply an IP address and enable the interface. Observe that the exit command is issued to move up just one level from the interface sub-mode to the global configuration mode.

Line Console Configuration Mode

This sub-mode or context allows you to make changes to the serial connection used to manage the router itself. The commands used here show some of the options that may be used here:

NETWORK-plus(config)#line console 0     
NETWORK-plus(config-line)#logging synchronous
NETWORK-plus(config-line)#no exec-timeout    

In this configuration, the router has been instructed to not disconnect the console session with the exec-timeout command, and not to confuse the user with unsolicited messages until after the user prompt is returned. Note that in this example, the line configuration sub-mode is exited by using the ctrl-Z key. This is processed the same as the end command that returns to the privilege EXEC prompt.


After making these configuration changes it is simple to verify the changes. Just like the necessity to navigate to the proper sub-mode contexts to make configuration changes, it is necessary to specify what sub-modes you wish to observe with the show command. Show is one of the most basic and versatile tools that a router offers us as administrators. As an example, to see the configuration changes you just made to the running configuration of FastEthernet0/0 you will use the show command and specify both running-configuration and the interface section you wish to look at:

NETWORK-plus#show running-config interface FastEthernet0/0
Building configuration...

Current configuration : 92 bytes
interface FastEthernet0/0
 ip address
 duplex auto
 speed auto


Save Running Config

There would be little point to making configuration changes unless the capacities to store those changes exist. To prevent configuration changes from being lost, it is necessary to manually save those configurations. The issue is that the command to save these configurations is not as intuitive as you would first expect. The method used to save the current running configuration is to copy it to the over the current start-up configuration:

NETWORK-plus#copy running-config startup-config 
Destination filename [startup-config]? 
Building configuration...

Now the changes have been saved, and your configurations will survive a restart.


This article has covered the most basic aspects of configuring a router. The intent was not to provide a complete end-to-end configuration tool, but rather an explanation of the most fundamental mechanisms behind how an IOS router processes commands to allow a user to make configuration changes. Routers are far less intuitive with regard to their functionality, and offer no real features until they are configured using the command line interface, thus making it very important to understand how to correctly configure them.

Pearson IT Certification Promotional Mailings & Special Offers

I would like to receive exclusive offers and hear about products from Pearson IT Certification and its family of brands. I can unsubscribe at any time.


Pearson Education, Inc., 221 River Street, Hoboken, New Jersey 07030, (Pearson) presents this site to provide information about Pearson IT Certification products and services that can be purchased through this site.

This privacy notice provides an overview of our commitment to privacy and describes how we collect, protect, use and share personal information collected through this site. Please note that other Pearson websites and online products and services have their own separate privacy policies.

Collection and Use of Information

To conduct business and deliver products and services, Pearson collects and uses personal information in several ways in connection with this site, including:

Questions and Inquiries

For inquiries and questions, we collect the inquiry or question, together with name, contact details (email address, phone number and mailing address) and any other additional information voluntarily submitted to us through a Contact Us form or an email. We use this information to address the inquiry and respond to the question.

Online Store

For orders and purchases placed through our online store on this site, we collect order details, name, institution name and address (if applicable), email address, phone number, shipping and billing addresses, credit/debit card information, shipping options and any instructions. We use this information to complete transactions, fulfill orders, communicate with individuals placing orders or visiting the online store, and for related purposes.


Pearson may offer opportunities to provide feedback or participate in surveys, including surveys evaluating Pearson products, services or sites. Participation is voluntary. Pearson collects information requested in the survey questions and uses the information to evaluate, support, maintain and improve products, services or sites; develop new products and services; conduct educational research; and for other purposes specified in the survey.

Contests and Drawings

Occasionally, we may sponsor a contest or drawing. Participation is optional. Pearson collects name, contact information and other information specified on the entry form for the contest or drawing to conduct the contest or drawing. Pearson may collect additional personal information from the winners of a contest or drawing in order to award the prize and for tax reporting purposes, as required by law.


If you have elected to receive email newsletters or promotional mailings and special offers but want to unsubscribe, simply email information@informit.com.

Service Announcements

On rare occasions it is necessary to send out a strictly service related announcement. For instance, if our service is temporarily suspended for maintenance we might send users an email. Generally, users may not opt-out of these communications, though they can deactivate their account information. However, these communications are not promotional in nature.

Customer Service

We communicate with users on a regular basis to provide requested services and in regard to issues relating to their account we reply via email or phone in accordance with the users' wishes when a user submits their information through our Contact Us form.

Other Collection and Use of Information

Application and System Logs

Pearson automatically collects log data to help ensure the delivery, availability and security of this site. Log data may include technical information about how a user or visitor connected to this site, such as browser type, type of computer/device, operating system, internet service provider and IP address. We use this information for support purposes and to monitor the health of the site, identify problems, improve service, detect unauthorized access and fraudulent activity, prevent and respond to security incidents and appropriately scale computing resources.

Web Analytics

Pearson may use third party web trend analytical services, including Google Analytics, to collect visitor information, such as IP addresses, browser types, referring pages, pages visited and time spent on a particular site. While these analytical services collect and report information on an anonymous basis, they may use cookies to gather web trend information. The information gathered may enable Pearson (but not the third party web trend services) to link information with application and system log data. Pearson uses this information for system administration and to identify problems, improve service, detect unauthorized access and fraudulent activity, prevent and respond to security incidents, appropriately scale computing resources and otherwise support and deliver this site and its services.

Cookies and Related Technologies

This site uses cookies and similar technologies to personalize content, measure traffic patterns, control security, track use and access of information on this site, and provide interest-based messages and advertising. Users can manage and block the use of cookies through their browser. Disabling or blocking certain cookies may limit the functionality of this site.

Do Not Track

This site currently does not respond to Do Not Track signals.


Pearson uses appropriate physical, administrative and technical security measures to protect personal information from unauthorized access, use and disclosure.


This site is not directed to children under the age of 13.


Pearson may send or direct marketing communications to users, provided that

  • Pearson will not use personal information collected or processed as a K-12 school service provider for the purpose of directed or targeted advertising.
  • Such marketing is consistent with applicable law and Pearson's legal obligations.
  • Pearson will not knowingly direct or send marketing communications to an individual who has expressed a preference not to receive marketing.
  • Where required by applicable law, express or implied consent to marketing exists and has not been withdrawn.

Pearson may provide personal information to a third party service provider on a restricted basis to provide marketing solely on behalf of Pearson or an affiliate or customer for whom Pearson is a service provider. Marketing preferences may be changed at any time.

Correcting/Updating Personal Information

If a user's personally identifiable information changes (such as your postal address or email address), we provide a way to correct or update that user's personal data provided to us. This can be done on the Account page. If a user no longer desires our service and desires to delete his or her account, please contact us at customer-service@informit.com and we will process the deletion of a user's account.


Users can always make an informed choice as to whether they should proceed with certain services offered by Adobe Press. If you choose to remove yourself from our mailing list(s) simply visit the following page and uncheck any communication you no longer want to receive: www.pearsonitcertification.com/u.aspx.

Sale of Personal Information

Pearson does not rent or sell personal information in exchange for any payment of money.

While Pearson does not sell personal information, as defined in Nevada law, Nevada residents may email a request for no sale of their personal information to NevadaDesignatedRequest@pearson.com.

Supplemental Privacy Statement for California Residents

California residents should read our Supplemental privacy statement for California residents in conjunction with this Privacy Notice. The Supplemental privacy statement for California residents explains Pearson's commitment to comply with California law and applies to personal information of California residents collected in connection with this site and the Services.

Sharing and Disclosure

Pearson may disclose personal information, as follows:

  • As required by law.
  • With the consent of the individual (or their parent, if the individual is a minor)
  • In response to a subpoena, court order or legal process, to the extent permitted or required by law
  • To protect the security and safety of individuals, data, assets and systems, consistent with applicable law
  • In connection the sale, joint venture or other transfer of some or all of its company or assets, subject to the provisions of this Privacy Notice
  • To investigate or address actual or suspected fraud or other illegal activities
  • To exercise its legal rights, including enforcement of the Terms of Use for this site or another contract
  • To affiliated Pearson companies and other companies and organizations who perform work for Pearson and are obligated to protect the privacy of personal information consistent with this Privacy Notice
  • To a school, organization, company or government agency, where Pearson collects or processes the personal information in a school setting or on behalf of such organization, company or government agency.


This web site contains links to other sites. Please be aware that we are not responsible for the privacy practices of such other sites. We encourage our users to be aware when they leave our site and to read the privacy statements of each and every web site that collects Personal Information. This privacy statement applies solely to information collected by this web site.

Requests and Contact

Please contact us about this Privacy Notice or if you have any requests or questions relating to the privacy of your personal information.

Changes to this Privacy Notice

We may revise this Privacy Notice through an updated posting. We will identify the effective date of the revision in the posting. Often, updates are made to provide greater clarity or to comply with changes in regulatory requirements. If the updates involve material changes to the collection, protection, use or disclosure of Personal Information, Pearson will provide notice of the change through a conspicuous notice on this site or other appropriate way. Continued use of the site after the effective date of a posted revision evidences acceptance. Please contact us if you have questions or concerns about the Privacy Notice or any objection to any revisions.

Last Update: November 17, 2020