Lab 1-7 – Configuring The Free CCNA Workbook GNS3 Topology

In this lab you’ll be importing the Free CCNA Workbook dot com Lab topology into GNS3. This is required if you have not built a physical lab to use with this website.

Real World Application

Real world application does not apply to this lab however in this lab you will learn how to configure the Free CCNA Workbook GNS3 topology which is used on 95% of all labs found in the Free CCNA Workbook.


Lab Prerequisites

  • Have GNS3 installed and the GNS3 environment variables configured which include the working directory, execution path, IOS Image directory and temp paths. If you do not have this completed than check out labs 1-5 – Installing Graphical Network Simulator v3 and 1-6 – Basic Graphic Network Simulator v3 Configuration
  • Have the Cisco IOS images listed in the previous lab extracted and located in the images location for the c3725 and c3640 platforms.
  • Ensure that the 3725 and 3640 platforms are configured in the Stub Area Networking GNS3 topology file before importing the Free CCNA Workbook Lab Topology or the importation will Fail.

Lab Objectives

  • Download and Import the Free CCNA Workbook Lab Topology file.
  • Successfully start all routers in the Lab Topology and apply an Idle PC Value to each device.
  • Familiarize yourself with the Free CCNA Workbook Topology by viewing the GNS3 topology or by visiting the Topology page found in the main navigation bar across the top of the page.

Lab Instruction

Step 1. First off you’ll need to ensure you’ve downloaded the Free CCNA Workbook GNS3 topology file by clicking the link on the left hand side bar or by clicking HERE!

Step 2. After you’ve downloaded the Free CCNA Workbook GNS3 topology file, extract it to your desktop or a folder that you store files to.

Read Me

As of GNS3 0.7.3 you will need to MANUALLY configure the image file location for each router in the Free CCNA Workbook topology configuration file using a text editor. Failure to do so will give you a frame relay error “link not connected” when attempting to import the topology.

Step 3. Load the GNS3 topology by double clicking on the file, GNS3 should load automatically and import the topology.

Step 4. After GNS3 loads and the topology is imported, you can then start R1 by right clicking on R1 and clicking start on the context menu. Once you’ve started this device, you can right click the device again and click Console to bring up the Putty terminal emulation window. This will present you with console access to R1 in the topology.

After making sure that the router has booted up into user mode; if prompted you can type “n” to skip the Initial Configuration Dialog and wait till you receive the prompt Router>


After you’ve received the user mode prompt you’ll need to wait about 10 seconds till the router is idling then you’ll need to configure the router with its own IDLE PC value. Dynamips is a very processor intensive application and each device running within Dynamips will need an IDLE PC value that can be applied to the device so the application can reduce the physical processor load. Note that an IDLE PC value is REQUIRED for each device.

Experiment with your IDLE PC values as these values are different on a per machine basis. Be sure to watch your processor utilization when experimenting with IDLE PC values to determine which values would best suit your machine. You can view your current processor utilization by starting task manager when clicking on your task bar; Afterward click on performance.

Once you’ve successfully started all devices in the topology and applied IDLE PC values to each device, you should then familiarize yourself with the Free CCNA Workbook topology. You can do so by clicking the Topology link in the top navigation bar or by clicking HERE!

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  1. mohamed, the URL has been updated.