Tag: gns3 how-to

GNS3: How to create Frame-Relay Hub and Spoke lab

When I first came in touch with GNS3 I had not idea how to work with it. Not because it is so complicate to operate, but because I didn’t saw any software like this one. GNS3 and Dynamips make a very good job together, allowing users to emulate a lot of network scenarios with different topologies. If using only Dynamips suppose that you edit all the configuration file manually in text mode, now with GNS3 you can drag and drop devices, connections and configure them on the fly.

For today, I prepared a presentation about how you can create a Frame-Relay hub and spoke topology in GNS3, save and use it whenever you need it. This tutorial does not include the configuration of the devices which form Frame-Relay hub and spoke, but only the GNS3 lab topology. If you are looking for the tutorial on how to  configure FR hub and spoke on Cisco routers, please refer to my previous tutorial.

The GNS3 lab topology which I’ll create in the following presentation is available for download here. Take the saved lab configuration and open it in your GNS3 software. Before you use it, please have a look inside the file, as there are some lines you suppose to modify to fit your system.

Please click on the image below to see the tutorial:

gns3-fr-hub-spoke

GNS3: How-to save multiple topology configurations for good

GNS3 is an extremely useful tool if you are using Dynamips to emulate Cisco devices. It is a graphical environment in which even a newbie can do complex configuration by clicking and dragging routers, switches, connections into a topology that can be saved.

The problem that occurred to me in the past (and maybe to you also) is the following. Let’s assume that we create a configuration with routers named R0 and R1 and you save the topology config and also the routers config (“copy run start”). All the files (GNS3 topology config and Dynamips files created for R0 / R1 saved config) will be put into the default GNS3 project directory (e.g. /tmp in Linux or other directory if you are using Windows system). For now it is perfect. You have everything fine.

Next time when you start a topology, by default GNS3 will start with the same routers R0 and R1, and we you boot them, they will load your ex-saved config files, because GNS3 will look for config files into it’s default project directory, and since the name of the routers are the same, it will think that this have to be loaded. So, what you will do when you have 10 topologies that you save. Give all the time different routers name? Even so you will end with a mess in your default GNS3 project directory.

I have a solution for this issue, that you might like. I’m not saying that I have discovered this solution…for sure there is somewhere out there on the Internet, but I think of it by my own and I said that maybe others will use it.

This how-to assume that you know what Dynamips, GNS3 and Linux (any distribution) are. The same steps can be applied on Windows system also. Please check the tutorial by clicking the image below:
*Note:  As the file is flash and it’s quite big please have patience until it is loaded*

GNS3 topology config save