Graphical Network Simulator-3 (GNS3) - Part II Installation on a Linux Server

Okay for Part II of GNS3, I came in today looking to install GNS3 on a Linux Server.

I noticed that GNS3 is designed to run on Ubuntu Linux, and as I tend to run in a CentOS7 shop, I am now faced with the hump of putting an Ubuntu server in here, or trying to get this to run on CentOS7. It should run on CentOS7, right? After all, this is a Linux world, right? 😏

I decided to take one of my 32Gb RAM servers, an HP box, that runs CentOS7, and follow a cookbook for installing GNS3 on it.

I followed this link:
https://gns3.com/discussions/how-to-install-gns3-on-centos-7-

I chose this box because it runs X Windows. It didn't have Python 3.6 on it, or the pip36 used for installing and managing python 3.6 packages.

A lot of steps in this thing.

Some questions I have about this cookbook that I need to look into:

1. Why does the cookbook use VirtualBox on Linux? I have KVM installed. Surely I can use that instead of VirtualBox. I only use VirtualBox on my Win10 laptop. So I have, for now, skipped that section.

2. What is IOU support? I will need to google that.

UPDATE: IOU (also called IOL, which stands for IOS on Linux, is basically an IOS simulator) that can run on an i386 chipset.  You would need and want that if you run any Cisco elements on the GNS3 simulator.

Graphical Network Simulator-3 (GNS3) - Part I Initial Introduction on a Laptop

Someone told me about this network modeling and simulation tool called Graphical Network Simulator-3. There is a Wikipedia page on this tool, which can be found here:

https://en.wikipedia.org/wiki/Graphical_Network_Simulator-3

Fascinating tool. Allows you to drag and drop network elements onto a canvas - but unlike the old tools, this tool can actually RUN the elements! To do this, you need to import image files as you drag and drop the elements out on the canvas. Below is an example of how, when dragging a simulated internet cloud onto the canvas will prompt for an image to run on a virtual machine.

Image Files Required for Network Elements in GNS3

Then, once you have the elements properly situated on the canvas, you can use a connector to interconnect them (it will prompt you for the NIC interface), and then, once your interconnection points are established, you can click a "run" button.

If all goes well everything turns green and packets start to flow. There is a built-in packet trace on each link line, which will dump packets to a file if you choose to do a packet capture.