Download Documentation Community Marketplace Training. How to install GNS3 with VirtualBox and use Cisco IOS images - this video shows you. Use nested virtualization with VirtualBox and run Cisco VIRL IOS images on the GNS3 VM. All the steps are shown.

You can gain experience by designing network topologies on GNS3 or use IOS images of real Cisco devices. By adding IOU devices to your network project, you can use the Cisco Layer 2 Switch and Layer 3 Switch.

How to Add IOU to GNS3 Server

You can easily use real Cisco Switch IOS in the GNS3 program. However, in order to fully utilize the Switches you add, you need to use IOU (IOS on Unix/Linux).

What is Cisco IOU?

First of all, let me briefly explain what IOU (IOS on Unix) is.

IOU stands for IOS on Unix / Linux. In short, they are Cisco IOS images running on Unix and Linux operating systems.

IOU functions are similar to Dynamips but use fewer resources. While Dynamips simulates the Cisco Router and Switch devices, you can add the same devices in the IOU structure.

In addition, as this structure is designed by Cisco employees for experimental purposes, it is strictly prohibited to distribute and reproduce these images to customers or any platform.

The biggest advantage of using this image is the ability to design more complex networks than Dynamips. In addition, the GNS3 VM virtual machine installed on an external drive provide more performance.

Additionally, you don’t have to fill your computer’s disk capacity with Cisco images and GNS3 projects.

Our recommendation; Inserting a high-speed SSD drive into the USB 3.0 external drive box makes it healthier and more efficient to use.

What is GNS3 VM?

In the early stages, GNS3 only simulated Cisco IOS images with Dynamips. Together with the development of the program, they provided for a solution due to Dynamips’ high resource usage while creating network designs and running GNS3 Server on the virtual machine, resulting in less resource usage.

How to Add and Run IOU Images on GNS3 Server

After briefly discussing what is IOS on Unix and GNS3 VM, let’s examine how to upload and use an image onto the server.

Step 1

Once you have the necessary tools, the first thing you do is to install the GNS3 VM. Double-click the setup file to start the installation.

Step 2

After running the VMware Workstation program, click the Import button to add the GNS3 OVA file to the virtual machine.

Step 3

Please wait while importing the GNS3 VM OVA file.

Step 4

Once the GNS3 OVA added to the virtual machine, run the VM.

Step 5

The first boot view of the GNS3 VM server is as follows.

Step 6

Opening GNS3 Server …

Step 7

Make a note of the IP address of the server and press the Enter key on the OK option to switch to Advanced Setup.

Step 8

On the Shell (Open a console) option, press Enter.

Step 9

You will need a license file to upload an IOU image to the GNS3 server.

Since the distribution of IOU images is prohibited, we have hidden some points during the licensing process.

Run the following commands to check the presence of the license file in the GNS3 Server root folder. If there is no license file, go to the next step.

Step 10

To access the GNS3 VM root folder, open the WinSCP program, type in the IP address of the server, type gns3 in the user name and password, and click Login.

Step 11

Click the Yes button on the security alert of the WinSCP program.

Step 12

Drag and drop the CiscoIOUKeygen.py file to the /home/gns3/root folder.

Step 13

Click OK to complete the process.

Step 14

After copying CiscoIOUKeygen.py to the GNS3 VM root directory, continue to the next step.

Step 15

Execute python3 CiscoIOUKeygen.py at the Shell command prompt of the GNS3 VM. Then, add the generated license number to the iourc.txt file.

Step 16

Create a text document named iourc.txt on your desktop, then write the license and save the file.

Step 17

Copy the iourc.txt file you created to the location where you installed the GNS3 VM.

Step 18

After running GNS3, select Local GNS3 VM and click Next.

Step 19

On the next screen, select VMware (Recommend) to continue. In this step, it will connect to the GNS3 Server automatically.

Step 20

Connecting to GNS3 Server …

Step 21

Before adding the IOU image on GNS3 Server, close the Add Virtual Machines window.

Dokumen program bimbingan dan konseling sd. Step 22

Click Edit / Preferences to complete the licensing process.

Step 23

In the window that opens, select IOS on UNIX and click Browse to add the iourc file in the right pane.

Step 24

Select the iourc.txt file you copied to the GNS3 server location and click the Open button.

Step 25

After adding the iourc file, click Apply to save the settings.

Step 26

Click IOU Devices and then click the New button to add Layer 2 and Layer 3 Switch.

Step 27

In the Server Type window that opens, select the Run this IOU device on the GNS3 VM option and click Next.

Step 28

Enter the Layer 2 Switch name you want to add, and then click Browse. In the Type field, specify the Switch layer.

Step 29

Select and add the Layer 2 Switch image.

Step 30

After adding Layer 2 Switch, click Finish.

Step 31

Once you have successfully added the Layer 2 Switch as in the image below, add an L3 Switch by clicking the New button again.

Step 32

Click Next in the Server Type window.

Step 33

Type Layer 3 Switch name and specify the type. Then click the Browse button to add the IOS image.

Step 34

Uploading Layer 3 Switch into GNS3 Server.

Step 35

Click Finish to upload the image to the server.

Step 36

Close the IOU Device Templates window after adding L3 Switch.

Step 37

Add the L2 and L3 Switch to the GNS3 workspace and run them.

Step 38

In the L2 Switch console window, test the device’s operability by creating one VLAN as an example.

Step 39

When you execute the show vlan command on the L2 Switch, you can see that a new VLAN created.

How to Configure IOS on Unix on GNS3⇒ Video

To use IOU images with GNS3, you can watch the video below and also subscribe to our YouTube channel to support us!

Final Word

In short, running IOU IOS images on GNS3 Server is more efficient. The use of these images is a major requirement for studying CCNP or CCIE exams. Thanks for following us!

Related Articles

♦ How to Update GNS3 VM
♦ How to Import GNS3 VM
♦ GNS3 and PortFast
♦ GNS3 and UplinkFast
♦ GNS3 and BackboneFast

In order to perform any router-based hands-on lab exercise in GNS3, first, you need to download ISO images for routers. After downloading IOS images, you need to add router IOS image in GNS3. In the previous posts, we have discussed a lot about how to download and use GNS3. In this post, we will explain how to add IOS image in GNS3. We assume that you have already downloaded, the router IOS images for GNS3. If you have not yet done it, click the following link to download the Cisco IOS image for GNS3.

Now, you need to add router IOS image in GNS3. To do so, you need to perform the following steps:

1. In the GNS3 console, click Edit and select Preferences to open the Preferences window. Click Next to add a new router IOS image in GNS3, as shown in the following figure.
2. In the IOS image page, select the New Image radio button, click Browse and select the router IOS image that you want to add in GNS3. In this case, e will use Cisco router c2691 IOS image. Click Next to proceed, as shown in the following figure.
3. In the Name and platform window, specify the name and platform for the IOS image and then click Next as shown in the following figure.
4. In the Memory page, set the desired Default RAM size and then click Next as shown in the following figure.
5. In the Network adapters page, ensure that slot 0 is already listed and selected. Select the additional slots, if required, and then click Next as shown in the following figure.
6. In the WIC modules page, select the WIC modules to add additional modules as per your requirement, and then click Next as shown in the following figure.
7. On the Idle-pc page, click Finish and then click OK to close the Preferences window.
8. In the GNS3 console, you can see that c2691 router is added. Drag it to the work view area as shown in the following figure. Right-click on the added router and then select Start to start it.
9. Open the console of the router as shown in the following figure and use it to perform the hands-on lab exercise in GNS3.
10. That’s all you need to do to add router IOS image in GNS3.

In this post, we have explained how to add IOS image in GNS3 and how to use routers in GNS3. Please let me know if you have stuck. We would love to hear you and your valuable feedback. You may like and share the post to others.