Book Image

GNS3 Network Simulation Guide

Book Image

GNS3 Network Simulation Guide

Overview of this book

GNS3 is an open-source Graphical Network Simulator used extensively by networking professionals to simulate networking devices such as Cisco, Juniper and Vyatta routers, along with Virtual PCs. GNS3 Network Simulation Guide gives you all the information you need to run a successful GNS3 simulation. You will be guided through the tricky installation pre-requisites and procedures involved in developing a simulated topology suitable for studying for Cisco CCIE Certification. We will also cover many useful tips and tricks which will help you make the most of your GNS3 simulator application. You will begin the GNS3 journey by ensuring that you have prepared your computer with any additional files required by GNS3, to set up the simulated environment needed for a successful installation process. Once GNS3 is installed, you will get to work creating a successful simulation including routers, Ethernet switches, Virtual PCs, and capture packets using Wireshark. Next, you will learn how to master GNS3's Graphical User Interface as well as the Command Console. The inner workings of GNS3 are described in depth so that you gain an appreciation of how UDP tunnels are used to tie the many components of GNS3 together. By following the clear examples and exercises in this guide, you will learn everything that you need to know about how to use GNS3 to prepare for certifications, as well as simulate real-world network scenarios.
Table of Contents (14 chapters)
GNS3 Network Simulation Guide
Credits
About the Author
About the Reviewers
www.PacktPub.com
Preface
Index

Cisco IOS


One feature of GNS3 that you might like to explore is the fact that if your physical topology includes some of the routers and interface options supported by GNS, you can use GNS3 to test various versions of IOS. The trick here is to know which version of IOS is suitable for your needs. The cisco Feature Navigator (available at http://tools.cisco.com/ITDIT/CFN/jsp/SearchBySoftware.jsp) can help, but in many cases you can often work out if an IOS image you are using supports the features you need simply by looking at the IOS name. Here is a way to decode image names.

Firstly, you have to understand the groupings of letters in the IOS name. They consist of up to seven major fields followed by a .bin extension:

[Platform]-[Feature Set]-[Memory location][Compression format].[Train number]-[Maintenance release].[Train identifier].bin

Take the following example:

c3725-adventerprisek9-mz.124-15.T10.bin

The full name of the image can be seen in the output of the show version command – for the...