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

Debugging using the GNS3 management console


You have already seen how useful the GNS3 management console is in observing the inner workings of GNS3, but so far I have only shown you two commands: debug 3 and show run. Using the help or ? command reveals that there are several more console commands:

=> help
Documented commands (type help <topic>):
========================================
aux      console  export  idlepc  push      save   stop      ver
capture  copy     filter  import  qmonitor  send   suspend 
clear    debug    help    list    reload    show   telnet  
confreg  end      hist    no      resume    start  vboxexec

Many of these commands are remnants left from the original Dynagen code and have better replacements in the GUI, but sometimes I find it easier to issue a command like show start than to check the topology.net file in a text editor.

Probably, the most useful commands as far as fine-tuning a router goes are the idlepc idlemax and idlepc idlesleep commands. Although...