"RedNectar" Chris Welsh likes to share knowledge, so it's no surprise that he spends most of his time teaching, some of his time consulting and too much of his time on forums and blogs. The teaching is mainly Cisco related (he became a CCSI in 1998), the consulting is through his own company (Nectar Network Knowledge) and his blog (http://rednectar.net), along with his contributions to the GNS3 Forum (http://forum.gns3.net), became the inspiration to write this book. To keep his sanity, he likes to go for long walks in bushland, particularly around the National Parks near his hometown of Sydney, Australia.

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.

What you will learn from this book

Install GNS3 on Windows, OS X, and Linux

Build simulations using Cisco routers, layer 3 switches, and Virtual PCs

Master the GNS3 Graphical User Interface

Tweak your favourite virtual terminal application , so that it will work with GNS3

Examine your simulated traffic with Wireshark

Manage your project’s files and directories

Include virtualized Windows or Linux computers into your simulations

Simulate Juniper and Vyatta routers

Learn about the GNS3 orchestration process which allows multiple simulated devices to communicate with each other

Debug using the GNS3 command console

Create complex multi-hosted environments for large scale simulations