Connecting to a Cisco Device via Console

Core Knowledge

So you take a brand new Cisco Router or switch out of the box and the very first thing you must do prior to installing it is to put a basic configuration on it. In order to configure the basics on a Cisco device you must first Console into the device.

If you ever take a brand new Cisco device out of the box you’ll see that it comes with a blue flat cable that has a DB9 serial connector on one end and a network RJ45 connector on the other. Don’t be fooled, this is not a “next generation” Ethernet cable or some token ring cable but rather a Cisco Console Cable.

You use this cable to connect to he Cisco device via Serial Port so you can configure the device using command line.

Because Cisco devices do not have graphics cards or the ability to use a mouse and keyboard, you must connect to the device using another computer that provides that functionality so you can configure the device via Console CLI.

In order to connect to a Cisco device via Console you’ll need to use a Terminal Emulator application.

Applications that you commonly use to perform this task can be Windows HyperTerminal which is included with Windows XP however Windows Vista and newer requires you to manually download/install this application.

An extremely popular terminal emulator is Putty which is completely free to download, you can get this by clicking the “Putty Terminal Emulator” link found in the useful links menu section in the footer.

The most popular paid terminal emulator is known as SecureCRT which is developed by VanDyke. This application at the time of writing this lab is $99 per single user license and supports SSH/Telnet/Serial and a bunch of other protocols commonly not used anymore. SecureCRT however provides extremely useful scripting functionality and logging capabilities along with the ability to save sessions in different folders so you can easily connect to existing equipment later.

In many situations in real life you may be required to connect to a Cisco device via console when you lock yourself out making an error in configuration such as misconfiguring an Access Control List or perhaps you peg the processor by executing a processor intensive debug command. None the less, as a Network engineer you must know how to console into a Cisco device.

Lab Prerequisites

In order to complete this lab you will need a real Cisco Router or Switch.



Prior to attempting this lab you must have a terminal emulator application installed such as HyperTerminal, Putty or SecureCRT.

Lab Objectives

To complete this lab you will perform the following objectives;

Before you Continue

It is recommended that you attempt to complete these lab objectives the first time without looking at the Lab Instruction section.



If you are a student preparing for the Cisco CCNA Certification Exam than you are more likely to remember how to complete these objectives if you attempt to complete them the first time on your own with the use of the core knowledge section found in this lab. You should only resort to the Lab Instruction section to verify your work.

Lab Instruction

While most terminal emulation software differs in available features and/or protocols, all terminal emulators achieve the same goal. In this walk through, Putty will be used, which is freely available (See Lab Summary) to connect to a Cisco device and establish a console session to the Cisco Command Line Interface.

Step 1: Connect your Cisco console cable or terminal adapter to a Serial port on your computer.

Step 2: Connect the RJ45 end of the console cable to the “Console” port on your Cisco Lab Access Server (Cisco 2509, 2511 or a Cisco router with a NM-xxA/S Network Module) do not power on your router yet.

Step 3: When first running the Putty executable you will be presented with the Putty Configuration Window as shown below;

Step 4: After the Putty configuration window appears, move the bullet from SSH to Serial;

Note: COM1 is the default communications port for Putty Serial communications; you may need to change your COM port to match the port which your console cable is connected to. 9600 BAUD is the default speed for Putty. 9600 is also the default speed for Cisco devices using the configuration register of 0×2102 (Configuration registers will be discussed in a later chapter)

Step 5: Once you’ve verified the COM port and Speed click “Open” and a new window will appear. This window will be the terminal window. Once the COM# – Putty terminal window has appeared, power on your Cisco Device. After the device has booted; assuming that the NVRAM is clear, you will be prompted with a Setup Configuration Dialog:

After you are presented with the Setup Configuration Dialog type “n” for no and press enter. You will then be prompted to press Return to Get Started!, after pressing Enter you will be at the routers user mode command line interface which looks like the following;

After you have reached this point you have completed the objectives of this lab. Proceed to Lab 1.3