Connecting GNS3 to real equipment

Connecting GNS3 to real equipment really could not be easier, and opens up a whole world of opportunities for the CCIE lab (or for that matter, any exam).

To start, connect your machine to the switch you are going to use and fire up GNS3.

Drag a cloud device to the main screen, and then right click and select configure.

Select the C1 node and from the device drop down select the device you are using to connect to the switch (i.e. the network interface).

Connecting GNS3 to real equipment

Click on Add, and then Apply and then close


Next, drag over a router of your choice and add a connection to the cloud device.


Start up the router and assign an IP address to the interface on the router that connects to the cloud device


Now, if all the interfaces are up and the lights are green,¬†you can issue the “show cdp neighbors” command and you should see your hardware attached!


Here we can see that the router is seeing the Cisco 3550 I have attached to the laptop that I am using. I have assigned an IP address to the Fas0/1 interface on the 3550, and can ping it from the R1 router:



Like I said, connecting GNS3 to real hardware really couldn’t be easier. The process is similar for Macs and Linux machines as well. There are a few differences, but nothing too complicated. You will need to download TunTap to be able to do this. Following the same steps as above, you will need to select “NIO TAP” and select the /dev/tap0 interface from the drop-down list. It may not necessarily be tap0, but you can find the interface by using the command:

ls -l /dev | egrep 'tap|tun'

In a future post, we will look at how to connect IOU to real equipment as well.