What is GNS3 Appliances?

GNS3 appliances are pre-defined device templates. Typically, to emulate a Cisco IOS router or other device on GNS3, you must first create a template. By importing an appliance file (.gns3a), you can easily create a template for the device you wish to emulate.

You can download verified appliance files from the GNS3 Web site’s Marketplace.

You may be thinking, “I can use any appliance in the marketplace?” But it is not so easy. The required image files must be prepared separately. Open source software, such as Ubuntu, can be downloaded when importing the appliance. But for proprietary software, such as Cisco IOS, you have to prepare the image file in advance.

GNS3 appliance import procedures

The procedure for importing a GNS3 appliance and creating a template is as follows

  1. Download the appliance file (.gns3a)
  2. Import appliance files to GNS3

In the following, we will import the Firefox appliance, which will be a handy web browser client.

Download the appliance file (.gns3a)

Download the Firefox appliance file from the GNS3 Web site’s Marketplace.

This appliance has Firefox installed on Tiny Core Linux emulated by Qemu on GNS3 VM.

Download the appliance file (.gns3a)Import appliance files to GNS3

Specify the appliance file you want to import from [File] -> [Import appliance] on GNS3.

Then follow the on-screen instructions to create the template defined in the appliance file. Basically, you can just specify the options selected by default and proceed with [Next].

When the appliance import is complete, the template defined in the appliance file has been created. If you look at [Edit]->[Preferences]->[Qemu VMs], you will see that a Firefox template has been created.

Once you have successfully created a template, you can then place it in your workspace and use the Firefox web browser. The following shows a Firefox client bridged to the host OS network and connected to the Internet.