When building networks, it is important to first have a test environment before deploying the final network infrastructure. Building a test environment can be expensive since it will require the organization to invest in additional hardware. However, with the existence of software network simulators, it has made possible for the organizations to carry out tests, troubleshooting and trying out different network models before they come up with a final optimized network infrastructure. GNS3 is one of the mostly used network simulators worldwide.

So what exactly is gns3? Short for graphical network simulator, gns3 was originally developed to simulate Cisco networks. However, it has since grown to become a multi-vendor network simulator attracting massive downloads all around the world. It allows you to easily add image ios and to just drag and drop then to the working environment to create a lab.

What are the benefits of using GNS3?

  • It is a multi-vendor network simulator
  • It can simulate complex networks
  • Gns3 is free open-source software
  • It is possible to do packet capture for the devices in the lab environment
  • The simulated infrastructure can be connected to the actual network set-up.

How can I install GNS3 on Linux Mint 20? In this guide, we are going to look at how to install GNS3 on Linux Mint 20.

Step 1: Update your Linux system

Before carrying out any installation, ensure that your system is running the latest updates using the below commands. Once update, ensure to reboot your system.

sudo apt-get update -y
sudo apt-get upgrade -y
sudo reboot

Step 2: Add GNS3 repository to your Linux Mint 20.

sudo apt-add-repository ppa:gns3/ppa
sudo apt update

Install GNS3 on Linux Mint 20

sudo apt install gns3-gui gns3-server -y

You will be prompted to allow non root users to run GNS3. Select Yes

The next prompt will be to allow non superusers to capture packets. Select Yes as well

Next allow IOU support with the following commands

sudo dpkg –add-architecture i386
sudo apt update
sudo apt install -y gns3-iou

GNS3 Docker Integration

To integrate Docker with GNS3, you need to install docker in your GNS3 Linux Mint. Check our guide on how to install Docker CE on Linux Mint 20. After installing Docker CE, you need to add your user to the following groups: ubridge, libvirt, kvm, wireshark and docker. Add your user to the groups as per the commands below:

sudo usermod -aG ubridge lorna
sudo usermod -aG libvirt lorna
sudo usermod -aG kvm lorna
sudo usermod -aG wireshark lorna
sudo usermod -aG docker lorna

Configuring GNS3

By this time GNS3 has been installed on your Linux Mint 20. Once you launch it, you will get a page as shown:

Select run appliances on my local machine and click next.

In the next page, choose your server local configuration and click next.

Connection to the local GNS3 server is now successful. Click next and in the next page, click finish after which you will be prompted to create a project.

Ready to start a GNS3 project

How to Create GNS3 Project

Before you start your project, exit GNS3 and connect back to refresh the user permissions. To start a GNS3 project, you need to have IOS images uploaded to your GNS3 environment. On the left pane, click on the device icons to choose an image you are going to use. Drag the devices to the working area to create your network.In my small example, I have connected two vPCs to an Ethernet switch. Check how to add IOS images to GNS3.

How to start GNS3 devices and open device console

To start the PCs, right click on each of them and select start. Click on Console to launch a device console.

To start capture, right click on the link and choose start capture

Networking Video courses to try.

Enjoy your network simulation with GNS3! Check more Linux guides below:


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