This tutorial explains how to install and configure GNS3 Server on the local system. Learn GNS3 setup wizard configuration and options.
GNS3 consists of two components: the GNS3 client and the GNS3 server. GNS3 client provides a GUI interface to create and test network topologies. GNS3 server stores and runs the devices you use in the network topologies.
To use GNS3, you need to install and configure both components. I have already explained the installation and configuration process of the client part in the previous tutorial. In this tutorial, we will learn the installation and configuration process of the GNS3 server.
This tutorial is the fifth part of the tutorial "GNS3 Setup Guide to practice CCNA/CCNP exam topics". The other parts of the tutorial are the following.
What are GNS3-all-in-one and GNS3-VM
Differences between Emulation and Simulation
Differences between Packet Tracer, GNS3, and Cisco VIRL
How to Install GNS3 Step by Step Explained
GNS3 server
You have three options to install the GNS3 server: the local system without a virtual machine, the local system with a virtual machine, and the remote server with a virtual machine. Depending on your requirement and system configuration, you can choose any option from these three options.
The first option needs less hardware configuration but supports limited devices. This setup is the best if your computer has less hardware configuration or you want to create only small networks.
The second option needs moderate hardware configuration but supports sufficient devices to create small and mid-size networks. This setup is the best if you want to use GNS3 to practice CCNA/CCNP exam topics.
If your computer has the following hardware configurations, you should use the second option to install the GNS3 server. If your computer has lower hardware configurations than the following configurations, you can use the first option to install the GNS3 server.
| Operating System | Windows 10 or later |
| Processor | Dual-core or higher |
| RAM | 8GB or more |
| Available Storage space | 40 GB |
The third option requires a remote server and a computer or laptop with bigger RAM, CPU, and hard disk. This setup is the best if you want to use GNS3 to test live networks. You do not need this setup to practice the CCNA/CCNP exam topics. Since this setup is not required to practice CCNA/CCNP exam topics, we will discuss this setup in another tutorial separately.
In this tutorial, we will discuss and learn how to install the GNS3 server on Windows using the first and second options.
GNS3 server setup on the local system
Installing and configuring the GNS3 server on the local system without a virtual machine is the first and the easiest option. To use this option, you don’t need any additional setup or configuration on the local system. The GNS3 client includes all necessary components to use the local system as the GNS3 server.
To configure the local system as a GNS3 server, start the GNS3 client. When the GNS3 client starts the first time, it automatically starts the Setup Wizard. The Setup Wizard allows you to configure the GNS3 server. You can also start the Setup Wizard anytime from the Help menu. Click the Help menu and click the Setup Wizard option.
On the first screen of the Setup Wizard select the second option "Run appliances on my local computer" and click Next.
On the next screen, you need to configure three options: Server Path, Host binding, and Port.
Server Path
When you install the GNS3 client, the installation process automatically installs the GNS3 server component. The installation process installs this component in the installation directory of the GNS3 client. You can use the Browse option to select it.
Host binding
The local GNS3 server runs on this IP address. The wizard offers many IP addresses to choose from in the drop-down. Although you can use any available IP address from the drop-down, you should use the IP address 127.0.0.1. This IP address belongs to the loopback interface. It provides the most error-free environment to the applications that run a server process on the local system.
Port
The local GNS3 server accepts connections from GNS3 clients on this port. You can use any available TCP port.
By default, the wizard automatically configures these values. Click Next to continue.
The wizard starts the GNS3 server and connects the GNS3 client to the GNS3 server on the selected IP address and port number.
On the next screen, it displays the result. If it shows the message "Connection to the local GNS3 server has been successful", it verifies that the local GNS3 server has been set up successfully.
On the last screen, it displays the summary of configuration settings it used to start the local GNS3 server and connect the GNS3 client to the GNS3 server. Click Finish.
Now, you can use GNS3 to create and test network topologies. This setup supports only limited devices such as legacy IOS images, VPCS, built-in-hub, switches, etc.
GNS3 server setup on a virtual machine
If you want to use GNS3 to practice CCNA/CCNP exam topics, this setup is the best. To use this setup, you need to download GNS3 server virtual machine. GNS3 provides pre-built customized GNS3 server virtual machines for VMware, VirtualBox, and Microsoft Virtual PC. Microsoft Virtual PC and VirtualBox are free. VMware is paid software.
In this tutorial, we will use VMware Workstation. You can use any virtualization software that you prefer. The installation and configuration process for all virtualization software is the same.
Download the pre-built virtual machine for your virtualization software from the following webpage.
https://www.gns3.com/software/download-vm
After downloading the virtual machine, open the folder that contains the downloaded file. Select the GNS3 server file and right-click and click the Extract all option.
Now start the VMware workstation and click File and click Open
Select the extracted file and click Open
VMware Workstation opens the file in the Import Virtual Machine wizard. Set the name "GNS3 VM" for the virtual machine and select the destination folder where you want to store the virtual machine. Select the folder on the partition that has at least 20GB of free disk space.
Click Import.
Importing process may take a few minutes.
VMware Workstation lists the imported machine in the left pane.
Now, open the GNS3 client and start the Setup Wizard again. Select the first option "Run appliances in a virtual machine" and click Next.
Even though you want to use a virtual machine to run virtual devices, still you need to configure the GNS3 local server. GNS3 client connects to GNS3 local server. GNS3 local server checks whether a GNS3-VM Server virtual machine is present. If it presents, it runs virtual devices inside it. If it is not present, it runs virtual devices on the host system.
The next screen allows you to configure a local server. We have already discussed the options available on the next screen. The wizard automatically selects the correct value. If it does not select, select the correct value and click Next.
The wizard configures and starts the local server. The next screen verifies the same. Click Next.
The wizard finds the GNS3 Server virtual machine in VMware Workstation. If it finds the virtual machine, it automatically starts the virtual machine. If it does not find the virtual machine or you have multiple virtual machines, on the next screen, you can manually tell the wizard which virtual machine to use.
Select your virtualization software and the virtual machine and click Next.
The wizard starts the selected virtual machine and shows a summary of settings on the next screen. Click Finish.
To verify the setup, you can check the Servers Summary and Console panes. The Servers Summary pane shows the current state of the running servers. It must show the local server and virtual machine in the running state. The Console pane shows logs. If the wizard fails to start the virtual machine or connect to the virtual machine, it lists the reasons and errors in the Console pane.
Troubleshooting
If you encounter errors or your setup does not work, you can use the following troubleshooting tips.
If the installation or configuration fails, restart the system before trying again. When you install or configure a local server or a virtual machine, it starts many processes in the background. If the installation or configuration fails, these processes remain active in the background and prevent you from starting them again. A system restart terminates all processes.
Temporarily disable Windows firewall and anti-virus program. If it solves your problem, you need to allow the gns3server, ubridge, and dynamips in your anti-virus program.
If you get the connection refuse error, use the following steps. Restart the computer, open command prompt, run the ipconfig/all command, note down the IP address listed under the VMnet1 interface, open GNS3, start the Setup Wizard again, use the noted IP address to connect the local GNS3 server.
Video version
This tutorial is also available in video format on our YouTube channel.
That’s all for this tutorial. In this tutorial, we learned how to setup GNS3 server on the local system to run virtual devices from the local system and virtual machine.