Are you sure you want to cancel your subscription?

If you cancel, your subscription will remain active through the paid term. You will be able to reactivate the subscription until that date.

Sorry to see you go

Your subscription will remain active until . If you change your mind, you may rectivate your subscription anytime before that date.

Are you sure you want to reactivate?
Welcome Back!

Your subscription has been reactivated and you will continue to be charged on .

Reactivate Subscription

Thank you for choosing to reactivate your subscription. In order to lock in your previous subscription rate, you owe: .

Your Subscription term is from - .

Questions? Call Sales.

Payment Due:

Auto-Renew Subscription

To auto-renew your subscription you need to select or enter your payment method in "Your Account" under Manage Payments.

Click continue to set up your payments.

CBT Nuggets License Agreement

Unless otherwise stated all references to “training videos” or to “videos” includes both individual videos within a series, entire series, series packages, and streaming subscription access to CBT Nuggets content. All references to CBT or CBT Nuggets shall mean CBT Nuggets LLC, a Delaware limited liability company located at 44 Country Club Road, Ste. 150, Eugene, Oregon.

A CBT Nuggets license is defined as a single user license. Accounts may purchase multiple users, and each user is assigned a single license.

  • GRANT OF LICENSE. CBT Nuggets grants you a non-transferable, non-exclusive license to use the training videos contained in this package or streaming subscription access to CBT content (the “Products”), solely for internal use by your business or for your own personal use. You may not copy, reproduce, reverse engineer, translate, port, modify or make derivative works of the Products without the express consent of CBT. You may not rent, disclose, publish, sell, assign, lease, sublicense, market, or transfer the Products or use them in any manner not expressly authorized by this Agreement without the express consent of CBT. You shall not derive or attempt to derive the source code, source files or structure of all or any portion of the Products by reverse engineering, disassembly, decompilation or any other means. You do not receive any, and CBT Nuggets retains all, ownership rights in the Products. The Products are copyrighted and may not be copied, distributed or reproduced in any form, in whole or in part even if modified or merged with other Products. You shall not alter or remove any copyright notice or proprietary legend contained in or on the Products.
  • TERMINATION OF LICENSE. Once any applicable subscription period has concluded, the license granted by this Agreement shall immediately terminate and you shall have no further right to access, review or use in any manner any CBT Nuggets content. CBT reserves the right to terminate your subscription if, at its sole discretion, CBT believes you are in violation of this Agreement. CBT reserves the right to terminate your subscription if, at its sole discretion, CBT believes you have exceeded reasonable usage. In these events no refund will be made of any amounts previously paid to CBT.
  • DISCLAIMER OF WARRANTY AND LIABILITY. The products are provided to you on an “as is” and “with all faults” basis. You assume the entire risk of loss in using the products. The products are complex and may contain some nonconformities, defects or errors. CBT Nuggets does not warrant that the products will meet your needs, “expectations or intended use,” that operations of the products will be error-free or uninterrupted, or that all nonconformities can or will be corrected. CBT Nuggets makes and user receives no warranty, whether express or implied, and all warranties of merchantability, title, and fitness for any particular purpose are expressly excluded. In no event shall CBT Nuggets be liable to you or any third party for any damages, claim or loss incurred (including, without limitation, compensatory, incidental, indirect, special, consequential or exemplary damages, lost profits, lost sales or business, expenditures, investments, or commitments in connection with any business, loss of any goodwill, or damages resulting from lost data or inability to use data) irrespective of whether CBT Nuggets has been informed of, knew of, or should have known of the likelihood of such damages. This limitation applies to all causes of action in the aggregate including without limitation breach of contract, breach of warranty, negligence, strict liability, misrepresentation, and other torts. In no event shall CBT Nuggets’ liability to you or any third party exceed $100.00.
  • REMEDIES. In the event of any breach of the terms of the Agreement CBT reserves the right to seek and recover damages for such breach, including but not limited to damages for copyright infringement and for unauthorized use of CBT content. CBT also reserves the right to seek and obtain injunctive relief in addition to all other remedies at law or in equity.
  • MISCELLANEOUS. This is the exclusive Agreement between CBT Nuggets and you regarding its subject matter. You may not assign any part of this Agreement without CBT Nuggets’ prior written consent. This Agreement shall be governed by the laws of the State of Oregon and venue of any legal proceeding shall be in Lane County, Oregon. In any proceeding to enforce or interpret this Agreement, the prevailing party shall be entitled to recover from the losing party reasonable attorney fees, costs and expenses incurred by the prevailing party before and at any trial, arbitration, bankruptcy or other proceeding and in any appeal or review. You shall pay any sales tax, use tax, excise, duty or any other form of tax relating to the Products or transactions. If any provision of this Agreement is declared invalid or unenforceable, the remaining provisions of this Agreement shall remain in effect. Any notice to CBT under this Agreement shall be delivered by U.S. certified mail, return receipt requested, or by overnight courier to CBT Nuggets at the following address: 44 Club Rd Suite 150, Eugene, OR 97401 or such other address as CBT may designate.

CBT Nuggets reserves the right, in its sole discretion, to change, modify, add, or remove all or part of the License Agreement at any time, with or without notice.

Billing Agreement

  • By entering into a Billing Agreement with CBT Nuggets, you authorize CBT Nuggets to use automatic billing and to charge your credit card on a recurring basis.
  • You agree to pay subscription charges on a monthly basis, under the following terms and conditions:
    • CBT Nuggets will periodically charge your credit card each monthly billing cycle as your subscription charges become due;
    • All payments are non-refundable and charges made to the credit card under this agreement will constitute in effect a "sales receipt" and confirmation that services were rendered and received;
    • To terminate the recurring billing process and/or arrange for an alternative method of payment, you must notify CBT Nuggets at least 24 hours prior to the end of the monthly billing cycle;
    • You will not dispute CBT Nugget’s recurring billing charges with your credit card issuer so long as the amount in question was for periods prior to the receipt and acknowledgement of a written request to cancel your account or cancel individual licenses on your account.
  • You guarantee and warrant that you are the legal cardholder for the credit card associated with the account, and that you are legally authorized to enter into this recurring billing agreement.
  • You agree to indemnify, defend and hold CBT Nuggets harmless, against any liability pursuant to this authorization.
  • You agree that CBT Nuggets is not obligated to verify or confirm the amount for the purpose of processing these types of payments. You acknowledge and agree that Recurring Payments may be variable and scheduled to occur at certain times.
  • If your payment requires a currency conversion by us, the amount of the currency conversion fee will be determined at the time of your payment. You acknowledge that the exchange rate determined at the time of each payment transaction will differ and you agree to the future execution of payments being based on fluctuating exchange rates.

CBT Nuggets reserves the right, in its sole discretion, to change, modify, add, or remove all or part of the Billing Agreement at any time, with or without notice.


The Definitive Guide for Working with GNS3

Course Duration: 10:35:46
Welcome to GNS3
"How good do you want to be?" A key ingredient to being very good at something is to have excellent instruction combined with lots of practice, practice, practice. This is true in areas such as flying a plane, becoming a doctor or being one of the best network engineers in the field. In the first Nugget of this GNS3 series, Keith introduces the idea of using virtualized hardware (running inside your computer) allowing you to practice your Cisco design, configuration and troubleshooting skills. The Graphical Network Simulator (GNS3) allows you to improve your skills as you build networks running live Cisco IOS, right inside of your computer. Keith also discusses some things that you can do to get the absolute most out of this video series, including the use of protocol analysis of the networks you create within GNS3.
GNS3: Up and Running on Windows
"I wish I could run a full topology of routers in an emulated environment without my PC pegging 100% CPU utilization." ~Quote from a new user of GNS3. In this video Keith walks you through the installation of GNS3 for Windows, identifying the two major reasons the processor goes too high to be of use anymore, and how to correct and avoid those problems. Topics covered in this video also include moving the IOS from a router to a PC, customizing folders to organize your GNS3 work and exec-timeout parameters for the console port of the router running in GNS3.
GNS3: Troubleshooting on Windows
"What happened, it was working yesterday!!!" This is an all too familiar phrase especially when working with GNS3. How could a fully working, idle PC optimized project fail to even open on the following day, and if does finally open why is the CPU back at 100%? In this Nugget Keith walks you through the reasons for this, and more importantly, how to detect and correct the issues that stand in the way between you and a happy GNS3 experience. Steps to prevent that from happening for future projects are also addressed in this video.
GNS3: Automating Initial Configurations
Whether its delivering water, manufacturing a product or providing a custom initial configuration to our routers in GNS3, automation can save us time and effort. In this video Keith shares with you some of his preferred startup configurations and how to automate them into brand new routers as you bring them into the GNS3 topology.
GNS3: Adding Hosts with Virtual PC Simulator
Imagine a bus, without anyone to ride it. Kind of pointless, isn't it? The purpose of our networks is to move data from devices attached to those networks. Adding hosts to our GNS3 networks is very useful for testing/verification that the network is configured correctly and that full connectivity exists, end to end. Using Virtual PC Simulator (VPCS) is a quick, free and low memory requirement option for adding hosts to GNS3. In this video Keith walks you through the process of getting VPCS, viewing and tweaking its startup file, and integrating it into a live GNS3 network.
GNS3: VirtualBox Host Integration
Adding a live Windows or Linux virtual machine to an existing GNS3 topology allows us the look and feel of a live network with hosts running real applications. One popular (and free) option for adding virtual machines is to use VirtualBox. In this video Keith walks you through the configuration required on both VirtualBox and GNS3 to allow devices from one world (hosts in VirtualBox) to play on the networks of the second world (routers in GNS3/dynamips). Free VirtualBox appliances are explained and demonstrated so you can begin using these hosts immediately!
GNS3: Integrating DHCP and the Host PC
We can sprinkle in virtual hosts as needed in our GNS3 topology, which is not only fun to do, but it can also assist in verification of our network design and security policies. As we move hosts around multiple subnets, we can save time by allowing the network to automatically assign addresses to these hosts using DHCP. In this Nugget we review how to integrate the virtual hosts and assign them an IP address automatically from the router's pool of addresses. We will also answer the question of "Can I add the real host computer to the GNS3 landscape?" to which the answer is a resounding YES. Let's get started right now!
GNS3: Connecting to the Internet
One of those "Wow!" moments is when you successfully issue a ping from a GNS3 router, and get a response from a device on a live network such as the Internet. In this video, Keith explains the requirements and then walks you through the implementation, troubleshooting and successful integration between the GNS3 topology and the Internet.
GNS3: Protocol Analyzer
Wireshark is a popular protocol analyzer that is closely integrated into dynamips/GNS3. By understanding how this tool can be used, learners can take a first-hand look at the actual segments, packets and frames that are traveling on their GNS3 networks. In this video Keith will walk you through how to use this tool in conjunction with GNS3 to view real-time network traffic, as well as how to save captures for later viewing.
GNS3: Custom Terminal Emulation
When working with terminal emulation, implementing small features can save lots of time and provide a more effective GNS3 session. One of these features is tabbed terminal sessions, which provide a separate tab for each network device to easily move between the devices in your topology. In this video Keith demonstrates how this can be done with SecureCRT or the free Putty application using a custom front-end named SuperPutty. Keith also walks you through some time-saving techniques for implementing virtual machines within GNS3, using VirtualBox Guest objects.
GNS3: Trunk to Live Equipment
A single Ethernet trunk can carry hundreds of VLANs, which becomes very important when a GNS3 topology needs to share multiple VLANs with a live rack of equipment. In this Nugget, Keith walks you through the logic and configuration to create a trunk within Windows GNS3 that connects to live gear and allows interaction between the virtual and physical worlds where each of the topologies reside.
GNS3: ASA Firewall
Practicing with the Adaptive Security Appliance (ASA) Firewall is critical to mastering that device, and we can add them to our GNS3 topology, along with the routers. In this Nugget, Keith walks you through the configuration, files and steps needed to integrate the ASA with GNS3. You will also learn how to add the ASDM (ASA Security Device Manager) GUI functionality to the virtual ASA. Troubleshooting steps are also discussed and demonstrated in relation to the ASA in GNS3.
GNS3: Ubuntu and Distributed Processing
What is the best operating system to use? The answer varies, but is also linked to what is available. In this video Keith walks you through the options for installing GNS3/dynamips on a Ubuntu system, and the fundamental steps of opening consoles and running the IdlePC process, very similar to what we did on Windows. In the second half of this video, Keith shares with you how to run the front end GNS3 on one computer, and have it use an external hypervisor which is running on a second machine. This can be very useful if a desktop or server with lots of CPU/memory is available and you want to leverage that resource.
GNS3: AWS Cloud Hosting
Everyone seems to be "going to the cloud" due to convenience, better ROI and better services. GNS3 and/or Dynamips are a great candidates for hosted services as larger amounts of CPU and memory are needed for ginormous topologies. In this video Keith discusses with you many of the options available, and then demonstrates a local PC running GNS3 while pointing to an external hypervisor that is running on an AWS Windows server in the cloud.
The Mac has gained mainstream popularity over the past few years, and Mac users also want the ability to use GNS3/Dynamips. In this video Keith discusses the requirements and demonstrates a couple of options for not only getting GNS3 going, but also how to integrate virtual machines using VirtualBox and even putting the host Macintosh machine in the GNS3 topology!
GNS3: L2 Ethernet Switching
Who says that GNS3 can't do switching? A lot of people, actually. In this Nugget, Keith discusses the opportunities for switching inside of GNS3 using switchport modules installed in the virtual routers. You and Keith will then create a full-blown topology that uses 4 L2 switches, Virtual PCS (VPCS), 4 VLANs, Router on a Stick for Inter-VLAN routing, spanning-tree tuning, access ports, 802.1q trunk ports and then NAT to connect the entire switched and routed infrastructure to the live Internet. And they said it won't do switching. ;)
GNS3: Connecting Virtual to Live Gear on the Mac
In each video you are building your skills regarding GNS3, discovering new options and learning how to configure them. In this Nugget, we are going to do that again, this time regarding connecting our Mac GNS3 topology to live gear, using either single connections or 802.1q Ethernet trunking. Keith also walks you through how to use the generic switch (if desired) to terminate a trunk from a live switch going to your GNS3 network.
GNS3: Trunking and Tunneling to Live Gear on Linux
Trunking can be done between Virtual and Physical gear in Windows, Mac OSX and Linux. In this video, Keith walks you through the details to make it happen when Ubuntu is the host OS. In addition, we will take a deeper dive into the configuration details of the external switches, including how to perform CDP tunneling through an external switch if you want to make a GNS3 device and physical device appear as CDP neighbors, even though they are not directly connected.
GNS3: Ubuntu, the ASA and Qemu
The ASA emulation provided by the Quick Emulator (Qemu) is similar between GNS3 on Windows and GNS3 on Ubuntu, with one big difference: The Qemu isn't installed by default by the Ubuntu software center when GNS3 is installed. On Windows the GNS3 all-in-one installer installs the Qemu for us. On Ubuntu we need to (as of Nov. 2012) manually install and patch the Qemu to work with the ASA. In this video, Keith provides a step-by-step install checklist for a manual install of all the GNS3/dynamips/Qemu software (the checklist is available in the NuggetLab download area for this series), and also shows the settings used to make it work. The video includes a demonstration of a working topology with the ASA in Ubuntu.
GNS3: Creating a Frame-Relay Switch
What do you call it when a company changes from leased lines to frame relay? Answer: The frame-relay switch ;). On a more serious note, the frame relay switch function provided by a Wide Area Network (WAN) service provider can be emulated inside of GNS3 using a couple different methods. The one you choose will be based on your preference. In this video Keith provides an overview of frame relay, then shares the options available to emulate the service provider network, and walks you through implementing both types.
GNS3: Cisco Configuration Professional
"Out with the old, in with the new." That happens a lot, especially with Graphical User Interface (GUI) management tools. One of the older Java based GUI IOS management application was named Security Device Manager (SDM). It has been shelved in favor of its replacement: Cisco Configuration Professional (CCP). In this video Keith introduces CCP, and then walks you through creating a new GNS3 network (from the ground up) that involves the bootstrap commands required on the IOS to allow CCP to work, all the way through using CCP to configure NAT and routing to allow a virtual host on the GNS3 network to successfully connect to the live Internet.
GNS3: NTP and CA Servers
Having your own Certificate Authority (CA) server integrated into your GNS3 topology can be very convenient. In this video Keith walks you through how to convert an IOS router into a CA server, as well as synchronizing your entire GNS3 network time with the Internet's time servers.

No Bookmarks

GNS3 is a free, open-source tool that provides emulation of network hardware (such as Cisco routers and firewalls), so that customers can practice, configure, and troubleshoot network scenarios all in a virtual environment running right on their Windows, Mac OSX or Linux computers. Multiple network topologies can be saved, paused and/or resumed on the fly so that the learner can practice at the convenience of their own schedule. GNS3 provides the emulation of the physical devices, and the user provides the OS image for the version/vendor of the software they want to practice on.

GNS3 is a fantastic tool, but there are a few stumbling blocks facing the typical user. In this video series, CBT Nuggets trainer Keith Barker becomes your tour guide and introduces the typical issues facing every GNS3 user and, more importantly, how to overcome and solve each of these challenges. Topics in the video series include running GNS3 in Windows, Mac and Linux environments; how to integrate virtual workstations into the GNS3 topology; how to connect the virtual GNS3 network to a live network; and much more.

Welcome to GNS3

00:00:02 - Welcome to the virtual world of GNS3.
00:00:05 - On behalf of the entire CBT Nuggets family, I'd like to be
00:00:09 - the first to welcome you.
00:00:10 - I'm Keith Barker.
00:00:11 - Let's begin.
00:00:13 - Our objective in this video is simple.
00:00:15 - It is to identify how you can get the absolute most out of
00:00:19 - our time together in this GNS3 series.
00:00:22 - I've learned that there's several different types of
00:00:24 - experiences that people have with GNS3.
00:00:26 - There's people who are brand new to it, who have never
00:00:29 - touched it.
00:00:29 - There's people who have been using it for years.
00:00:31 - And there's a whole wide range of everybody else in between.
00:00:35 - No matter where you are on that scale, this GNS3 series
00:00:39 - has something for you.
00:00:41 - Let's take a moment and identify why GNS3 is so
00:00:44 - valuable to so many people.
00:00:47 - Let's imagine that you and I and a few other friends are
00:00:49 - planning a trip.
00:00:50 - And we're going to go on an airplane.
00:00:51 - So we all meet early in the morning, and it's still cold,
00:00:54 - at the airport at 6:00 AM.
00:00:55 - We go through security.
00:00:56 - We get on the plane.
00:00:57 - And we discover, to our dismay, that the pilot,
00:01:01 - although he studied really hard, he's never actually
00:01:05 - flown a plane before.
00:01:06 - Neither has the co-pilot, but don't worry they've studied.
00:01:11 - We, you and I, are off of that plane.
00:01:13 - We are not flying with a guy who's never
00:01:16 - really flown before.
00:01:17 - Well, as silly as that sounds, we have the same challenge
00:01:20 - inside our computer networks.
00:01:21 - Let's take this network right here.
00:01:24 - We've got some switches and routers.
00:01:26 - We've got some WAN connections.
00:01:27 - We have an internet service provider.
00:01:29 - It's very unlikely that someone would trust you and I
00:01:33 - to work on this network had we never practiced hands-on
00:01:37 - configuring a network before.
00:01:38 - Even if we've studied in our minds and we've read and
00:01:41 - watched videos, it's important for us to practice.
00:01:44 - So for you and I to get our hands-on practice there's
00:01:47 - three basic things that we can do, actually four.
00:01:50 - One's kind of silly.
00:01:51 - One is to use Notepad.
00:01:53 - And just put in the commands--
00:01:56 - Notepad or a text editor-- and pretend that we're actually
00:01:59 - putting commands in.
00:02:00 - Now, I've seen people do that.
00:02:02 - And that doesn't work for me because there's no response
00:02:05 - from a text editor.
00:02:06 - So you put the command in and you press Enter.
00:02:08 - And you think it's right.
00:02:09 - You hope it's right.
00:02:10 - But that's not really a great reinforcement.
00:02:12 - The next option is we could go ahead use a simulator.
00:02:16 - Now that would also work for a pilot.
00:02:18 - Pilots have simulators.
00:02:19 - So they can practice and get a feel for it.
00:02:21 - And there's great simulators out there.
00:02:24 - So you can purchase a simulator.
00:02:25 - Practice with a simulator.
00:02:26 - You put the commands in, but it's not the real deal.
00:02:29 - It's simulated.
00:02:30 - The next option, which is cool, is hardware.
00:02:34 - Now, in many companies, you may have racks of hardware
00:02:37 - that you can put together.
00:02:39 - Or you can go out and purchase hardware.
00:02:41 - I love hardware.
00:02:42 - I have hardware in my lab here at my home office.
00:02:44 - Hardware is a great, great thing.
00:02:46 - What's the challenge though?
00:02:48 - Oftentimes, we don't have enough of it.
00:02:49 - If you have the hardware to practice with, it's not in
00:02:52 - production and you can go ahead and use it to
00:02:54 - reconfigure, that's fantastic.
00:02:56 - So if that option is open for you, go for it.
00:02:59 - The other option is to go ahead and use an emulator.
00:03:04 - An emulator pretends.
00:03:06 - It pretends to be something.
00:03:08 - For example, if you want to run a PC in a virtual
00:03:11 - environment, there's lots of virtual
00:03:13 - environments to run a PC in.
00:03:14 - For example, you have Virtual Box.
00:03:16 - You have VMware and others that can
00:03:19 - virtualize the hardware.
00:03:20 - So you might have an operating system like Windows.
00:03:24 - It's running inside of this virtual machine.
00:03:27 - It's not real.
00:03:28 - But the operating system doesn't know it.
00:03:30 - So the key is, when you bring up Windows and you run it, the
00:03:34 - Windows operating system doesn't know that it's not
00:03:36 - really running on physical hardware.
00:03:38 - It's logically in some bigger server somewhere.
00:03:41 - We can do that same thing with GNS3 because GNS3, and behind
00:03:45 - the scenes something called Dynamips, it's an emulator.
00:03:48 - If we do a show version right here and we do a show IP
00:03:56 - interface brief and we do anything else,
00:03:59 - this is live IOS.
00:04:01 - It's really running.
00:04:02 - It's not running on a real hardware platform.
00:04:05 - It's all virtualized.
00:04:07 - Now the benefit of that is, is that if we want to practice a
00:04:09 - network-- for example, let's say we're just dreaming and
00:04:12 - we're thinking, OK--
00:04:13 - so the light bulb's going off in our mind--
00:04:14 - I'd like to create a couple routers, a WAN link, a
00:04:17 - connection to the service provider, a switched
00:04:20 - environment, including spanning tree, we could
00:04:23 - actually do it.
00:04:23 - We could emulate all this stuff.
00:04:26 - And actually run the software and have it respond like it
00:04:29 - would on live gear, which is pretty darn amazing.
00:04:33 - So the biggest benefit of GNS3 is that it gives us an
00:04:36 - emulated environment where we can emulate the hardware, run
00:04:39 - live IOS software, and actually
00:04:42 - practice the commands.
00:04:43 - So the case is, before we roll this out, we could logically
00:04:47 - do it inside of GNS3.
00:04:49 - Practice all of it.
00:04:50 - And then have our design perfect before we roll it out
00:04:52 - on the production equipment.
00:04:55 - Another challenge that comes up all the time that makes
00:04:57 - GNS3 very, very powerful is the ability to validate what
00:05:00 - we think is happening.
00:05:01 - For example, one of the concepts that we learned about
00:05:04 - is this thing called DHCP.
00:05:05 - In fact, let me bring up a topology in GNS3 to show you.
00:05:09 - So let's consider this topology.
00:05:10 - Here we have DHCP.
00:05:12 - And this is the inside of the network from a NAT perspective
00:05:14 - and the outside of the network from a NAT perspective.
00:05:16 - This is R1.
00:05:17 - We have various interfaces.
00:05:18 - He's connected to the live internet.
00:05:20 - And everything from here over, this is all virtualized.
00:05:25 - The PC is virtualized.
00:05:26 - The router is virtualized.
00:05:27 - The connection to the Internet through my
00:05:29 - home network is real.
00:05:31 - And then of course, the internet's real as well.
00:05:33 - But if we wanted to verify basic concepts like DHCP
00:05:35 - what's supposed to happen?
00:05:37 - Well, what we learn in technical books is that, well,
00:05:40 - DHCP here's what supposed to happen.
00:05:42 - The client does a discover.
00:05:43 - The DHCP server sends an offer this way.
00:05:47 - The client requests that.
00:05:48 - And then the DHCP server sends an acknowledgement.
00:05:51 - So we have DORA, like Dora the Explorer.
00:05:54 - Now, that's great.
00:05:55 - And we can study that.
00:05:56 - But if we wanted to just confirm that that's really
00:05:58 - what's happening, one of my friend's Marvin says, Keith,
00:06:02 - the packets, they don't lie.
00:06:04 - So what we could do is we could actually capture traffic
00:06:06 - on this wire right here.
00:06:08 - Check this out.
00:06:09 - I could say--
00:06:09 - Oh, I have a capture running.
00:06:12 - Let me stop that capture.
00:06:13 - Let me start a new capture.
00:06:15 - And click OK.
00:06:17 - And then let's bring up that capture live.
00:06:19 - So I'm going to start Wireshark.
00:06:20 - So here's a capture of everything that's happening on
00:06:23 - that wire real-time.
00:06:25 - So if we wanted to actually see DHCP, we could bring up
00:06:28 - this virtual machine like this.
00:06:30 - And I'm going to just bring this over, so
00:06:32 - we can see it all.
00:06:33 - I'm going to right click on Disable
00:06:36 - for the network adapter.
00:06:38 - And then I've got to go back to Control Panel to start it.
00:06:41 - I'm going to start it again.
00:06:42 - And as I enable it, let's take a look right here at the
00:06:45 - packet capture.
00:06:46 - So that's capturing all of the traffic as it really happens
00:06:49 - on the wire, which is pretty darn amazing.
00:06:52 - So you might look at this and say, wow, this Windows
00:06:55 - machine-- it's Windows XP--
00:06:56 - what's all this traffic that's happening.
00:06:58 - Well, my friends, that's the native, natural traffic that
00:07:00 - that Windows machine is really going to generate.
00:07:03 - So I'm going to go ahead and stop this.
00:07:05 - And we'll scroll up.
00:07:06 - Let's take a look at the DHCP, which was really our
00:07:08 - important part here.
00:07:09 - If we wanted to verify how DHCP worked, we could simply
00:07:11 - open it up.
00:07:12 - Say, OK, here's our DHCP.
00:07:14 - Let me bring this a little bit bigger so we
00:07:16 - can see all of it.
00:07:19 - So here we have our discover, right here.
00:07:21 - That's the first packet.
00:07:22 - And the next packet, we have an offer from the server.
00:07:25 - Third packet, we have the DHCP request.
00:07:27 - And the fourth packet, we have the acknowledgement.
00:07:30 - And there's also ARPs and all the other traffic that you'd
00:07:32 - normally see on a production network.
00:07:34 - So if you really want to dig down for understanding the
00:07:38 - protocols, how they work, built in to the installation
00:07:42 - for the all-in-one installer for GNS3, it not only includes
00:07:45 - all the back end stuff like Dynamips, it also includes
00:07:48 - Wireshark and the drivers to make that all work.
00:07:51 - So you can just simply right click, start a capture, view
00:07:54 - it real-time if you want to.
00:07:55 - And as I forgot to do earlier, I'm going to go ahead and stop
00:07:58 - the capturing as well.
00:07:59 - Otherwise, that capture keep growing and growing up until
00:08:02 - the size limit that I set for it.
00:08:03 - So that is just an incredible feature that's very, very
00:08:07 - helpful not only for just designing networks, but also
00:08:10 - for verifying that the network is operating and the protocols
00:08:14 - are operating as you thought they were.
00:08:16 - And it never ceases to amaze me what I find when I look at
00:08:20 - my own GNS3 networks with the protocol analyzer.
00:08:23 - I'm always surprised.
00:08:24 - And it gives me an opportunity to dig deeper, and deeper, and
00:08:28 - deeper to find out what the real behavior of these
00:08:31 - protocols are, even ones I've thought I've known for many,
00:08:34 - many years.
00:08:36 - Another comment I get all the time is that, oh yeah, Keith,
00:08:38 - GNS3 is great.
00:08:40 - I love it.
00:08:41 - Once I got it dialed in, it was fantastic.
00:08:43 - However, it doesn't do switching.
00:08:44 - And I think to myself, OK, I know it doesn't do advanced
00:08:48 - switching like at the CCNP and CCIE level, however, for basic
00:08:53 - switching let's take a look at what it can do.
00:08:56 - We can do ether channel.
00:08:58 - We can do trunks, whether it's between switches or for a
00:09:01 - router on a stick configuration over to R1.
00:09:03 - We can do access ports.
00:09:05 - And we can use spanning tree.
00:09:08 - It also does VTP, if you care about VTP.
00:09:10 - So if you want to practice with some of those
00:09:13 - technologies, all of those that I just mentioned, are
00:09:16 - supported inside of GNS3.
00:09:18 - And I've got a Nugget to walk you through exactly how to do
00:09:21 - those aspects as well.
00:09:23 - I've had the opportunity to work with a lot
00:09:25 - of wonderful people.
00:09:26 - And sometimes in live class I would have an
00:09:28 - evening GNS3 workshop.
00:09:30 - So I'd say, OK, class is from 8:00 to 6:00 or 8:00 to 5:00,
00:09:34 - whatever it is, let's meet here at 6:30 and we'll spend
00:09:37 - two or three hours on a GNS3 workshop.
00:09:39 - And I'd have people show up every time.
00:09:41 - And people would bring their Macintosh.
00:09:43 - They would bring their Linux.
00:09:44 - They would bring their Windows machines.
00:09:46 - And I'd walk them through step-by-step how to
00:09:48 - systematically optimize get their machines up and
00:09:51 - running with GNS3.
00:09:52 - And they were always blown away.
00:09:54 - But you know what?
00:09:55 - There's some common, basic things that apply to all those
00:09:58 - platforms that if you do you can have success
00:10:01 - with GNS3 as well.
00:10:03 - So in that light, I have integrated into this series
00:10:06 - mostly Windows, but also some Mac and also some Linux.
00:10:10 - And here's what I'd like to ask you to do.
00:10:12 - Regardless of which platform you're running, I'd like you
00:10:16 - to watch all the videos in order.
00:10:18 - Now, why in order?
00:10:20 - Because every single Nugget, we're going to add some new
00:10:23 - concept to the mix.
00:10:25 - And a lot of the concepts apply across the board.
00:10:28 - So we'll build a foundation.
00:10:29 - And as we continue to go, we'll build the concepts, and
00:10:32 - build the features, and build the add-ons.
00:10:34 - So when you're done, you'll have this tool belt full of
00:10:37 - options that you can use when building
00:10:39 - your own GNS3 topology.
00:10:41 - Secondly, besides just watching the video, I would
00:10:45 - also like you to draw out-- have some scratch paper
00:10:48 - handy-- because I'd like you to draw out the topologies
00:10:50 - that you would like to do.
00:10:52 - It makes a lot of sense to do something like this.
00:10:54 - Before you go out and create something inside of a
00:10:57 - production network, or inside of GNS3 even, it's a great
00:11:01 - idea to have a plan.
00:11:02 - So for example, maybe an initial plan would be this, I
00:11:05 - want a router.
00:11:06 - And I want that one router to connect to router two.
00:11:09 - And this will be FA0/0.
00:11:12 - That'll be FA0/0.
00:11:14 - And this will be FA0/1, FA0/1.
00:11:19 - And this'll be a switch and a switch.
00:11:21 - And maybe not even hang a PC off of it yet.
00:11:25 - And maybe create a loop back and have a loop
00:11:26 - back here with
00:11:29 - And maybe a loop back here with
00:11:32 - And maybe a basic routing protocol, like EIGRP--
00:11:36 - little chuckle there-- or OSPF.
00:11:39 - And I'm not going to have you do RIP.
00:11:40 - Friends don't let friends do RIP.
00:11:42 - So do one of those two.
00:11:43 - So this would be a design.
00:11:45 - And that's why I talk about drawing.
00:11:47 - Plan out what you're going to do before you go ahead and
00:11:50 - attempt to do it.
00:11:51 - So once you plan this out, you'd also have to plant what
00:11:53 - addresses to use.
00:11:54 - So loop backs can be these.
00:11:55 - Maybe this is network, R1.1, R2.2.
00:12:00 - On these interfaces here, maybe
00:12:02 - this is 192 dot whatever.
00:12:04 - So plan out your network and draw it.
00:12:06 - So once you've drawn it out-- it could be a napkin.
00:12:08 - It could be a paper towel.
00:12:10 - It could be a desktop.
00:12:11 - As long as you're not doing any
00:12:12 - permanent damage to a desk.
00:12:14 - Write it out.
00:12:15 - And then go to GNS3 and create it.
00:12:18 - So that's what I would I encourage you to do.
00:12:19 - Watch all the videos.
00:12:20 - As I create the topologies, draw them out.
00:12:23 - And then, my friends, I would like you do most of them,
00:12:26 - whether you're on Mac, or whether you're on Linux, or
00:12:29 - whether you're on Windows.
00:12:30 - It doesn't really matter.
00:12:31 - The basic topology and putting the pieces together you can do
00:12:34 - on every single one of those platforms.
00:12:36 - I would strongly encourage you to do it.
00:12:38 - So after you've been through five or six videos, you're
00:12:40 - going to get very, very good at creating topologies and
00:12:44 - making them work.
00:12:45 - And here's a secret.
00:12:46 - There's a little thing that happens after you've done a
00:12:48 - few and it works, and you make a whole new one and it works,
00:12:52 - and a whole new and it works, your confidence level
00:12:54 - is going to go up.
00:12:56 - And then this whole thing about GNS3 itself, that won't
00:12:59 - become the obstacle to learning.
00:13:01 - You'll have GNS3 as a tool.
00:13:03 - So you can say, you know what?
00:13:05 - I want to take a look at MPLS and the labels.
00:13:07 - Or I want to take a look at IPsec and how IPsec
00:13:10 - encapsulates the data.
00:13:11 - You could throw those topologies together very
00:13:14 - quickly because you're comfortable with your GNS
00:13:17 - skills of putting that topology
00:13:19 - together and in place.
00:13:22 - I would like to ask one request of you.
00:13:24 - And that is, as we go through these videos together and as
00:13:27 - you start building your topologies, you're going to
00:13:29 - have a moment where you're going to say, oh my gosh.
00:13:34 - I can't believe that's working.
00:13:36 - That's great.
00:13:37 - Maybe it's your first GNS3 topology with R1 and R2.
00:13:42 - Or maybe it's a MPLS Layer 3 VPN infrastructure with
00:13:45 - service providers emulated and connected to live Internet and
00:13:48 - everything else.
00:13:49 - Whatever it is, what I would love you to do is take a
00:13:52 - snapshot of your topology.
00:13:53 - Take a picture of your topology and go ahead and post
00:13:56 - it up on my Facebook page, Keith Barker Networking.
00:14:00 - I would love to share the moment with you
00:14:03 - of the oh my gosh.
00:14:05 - So if you would, do me that huge favor.
00:14:08 - Don't do them for every topology because you're going
00:14:09 - to have dozens after you get running with this.
00:14:11 - But just take one that you're like, oh my gosh, I'm pretty
00:14:14 - proud of this.
00:14:15 - Grab an image of it.
00:14:16 - And paste it up on my Facebook page so that we can enjoy the
00:14:19 - moment together.
00:14:21 - I still get a kick out of it almost every time when I'm on
00:14:24 - a virtual machine and I'm going out to the live Internet
00:14:28 - from a virtual machine and it works because it's just so
00:14:30 - darn amazing.
00:14:32 - So in that light, let me also answer another question that
00:14:34 - comes up all the time.
00:14:35 - Well, Keith, what hardware models are supported inside of
00:14:39 - GNS3 for emulating hardware?
00:14:41 - What hardware can we emulate?
00:14:43 - Let me launch a browser from this PC.
00:14:45 - And let's go ask Google.
00:14:46 - So this right here is from this virtual machine.
00:14:50 - And let's go ahead and do GNS3 emulated hardware.
00:14:52 - And the top link walks us through the details of that.
00:14:55 - It's right from's website directly.
00:14:58 - And we scroll down.
00:14:59 - And it's going to talk about the models.
00:15:00 - So 1700s, 2600s, 3600s, 3700s, various network models,
00:15:08 - various 7200 series, and so it has a list of all the physical
00:15:13 - hardware that is supported.
00:15:14 - So I normally get one of my favorites that just works for
00:15:17 - me all the time and then I just use that over and over
00:15:20 - again for all of my router models.
00:15:21 - If I need to change it for some reason, I might mix it
00:15:24 - up, but that's a great idea as well.
00:15:26 - Grab one model that you're comfortable with, that works
00:15:29 - for you, and stick with it throughout your journey in
00:15:32 - working with GNS3.
00:15:34 - Another question I have all the time is, Keith, if I'm
00:15:36 - going through a Nugget, how do I optimize the time inside of
00:15:39 - that Nugget?
00:15:40 - And the answer is lab up everything you can as you go
00:15:43 - through the Nugget.
00:15:44 - See, one of the cool things about CBT Nuggets is
00:15:46 - you can pause us.
00:15:47 - Try it.
00:15:48 - Pause me right now.
00:15:49 - OK, and then you can bring me back.
00:15:50 - And that pause can be as long as you need it to be.
00:15:53 - So for example, if you're with me in the ASA firewall class
00:15:57 - and we're going through active active failover, you can pause
00:16:00 - me right in the middle of that and lab it up.
00:16:02 - Because the ASA is also supported inside of GNS3.
00:16:06 - I'll walk you through the steps of how to configure that
00:16:08 - and get that all working in this series.
00:16:11 - So don't just watch it and enjoy it and learn it.
00:16:14 - Internalize it by practicing.
00:16:16 - So that applies to the advanced courses all the way
00:16:19 - down to network plus.
00:16:20 - If you're in network plus and you're learning about ARP, lab
00:16:24 - up a simple network and have maybe FA0/0 an FA0/0 here.
00:16:29 - Put on a basic IP address.
00:16:31 - And in these videos I'm going to walk you through doing that
00:16:33 - several times.
00:16:34 - And then you can use protocol capture on that wire.
00:16:36 - And look at the ARP packets.
00:16:38 - And verify what's in them, how they worked, what was the
00:16:41 - Layer 2 addresses involved, what did the ARP request look
00:16:44 - like, DHCP, or any of the other protocols that are
00:16:47 - coursing through the veins of our network.
00:16:49 - You can not only see them, but you can also analyze them.
00:16:53 - I have had an absolute blast in putting this series
00:16:56 - together for you.
00:16:57 - And when I say for you, I'm serious.
00:16:59 - I did it as if you and I were sitting right next to each
00:17:02 - other side-by-side, enjoying the time logically going
00:17:05 - through each and every piece to get GNS3 successfully up
00:17:08 - and working on your computer.
00:17:11 - And I'm looking forward to seeing you in each and every
00:17:14 - Nugget in this series.
00:17:15 - I hope this has been informative for you.
00:17:18 - And I'd like to thank you for viewing.

GNS3: Up and Running on Windows

GNS3: Troubleshooting on Windows

GNS3: Automating Initial Configurations

GNS3: Adding Hosts with Virtual PC Simulator

GNS3: VirtualBox Host Integration

GNS3: Integrating DHCP and the Host PC

GNS3: Connecting to the Internet

GNS3: Protocol Analyzer

GNS3: Custom Terminal Emulation

GNS3: Trunk to Live Equipment

GNS3: ASA Firewall

GNS3: Ubuntu and Distributed Processing

GNS3: AWS Cloud Hosting


GNS3: L2 Ethernet Switching

GNS3: Connecting Virtual to Live Gear on the Mac

GNS3: Trunking and Tunneling to Live Gear on Linux

GNS3: Ubuntu, the ASA and Qemu

GNS3: Creating a Frame-Relay Switch

GNS3: Cisco Configuration Professional

GNS3: NTP and CA Servers

This forum is for community use – trainers will not participate in conversations. Share your thoughts on training content and engage with other members of the CBT Nuggets community. For customer service questions, please contact our support team. The views expressed in comments reflect those of the author and not of CBT Nuggets. We reserve the right to remove comments that do not adhere to our community standards.

comments powered by Disqus
Community Standards

We encourage you to share your wisdom, opinions, and questions with the CBT Nuggets community. To keep things civil, we have established the following policy.

We reserve the right not to post comments that:
contain obscene, indecent, or profane language; contain threats or defamatory statements; contain personal attacks; contain hate speech directed at race, color, sex, sexual orientation, national origin, ethnicity, age, religion, or disability; contributes to a hostile atmosphere; or promotes or endorses services or products. Non-commercial links, if relevant to the topic, are acceptable. Comments are not moderated, however, all comments will automatically be filtered for content that might violate our comment policies. If your comment is flagged by our filter, it will not be published.

We will be continually monitoring published comments and any content that violates our policies will be removed. Users who repeatedly violate our comments policy may be prohibited from commenting.
Keith Barker

Keith Barker

CBT Nuggets Trainer

Cisco CCDP, CCIE Security, CCIE Routing & Switching; Juniper JNCIS-ENT, JNCIS-SP; Brocade BCNP ; HP-MASE; (ISC)2 CISSP; CompTIA Network+, Security+

Area of Expertise:
Cisco, security, networking, bitcoin. Author or coauthor of: CCNA Security 640-554 Official Cert Guide; CCNP Security IPS 642-627 Official Cert Guide; CCNA Security 640-554 Official Cert Guide, and many more.

Course Features

Speed Control

Play videos at a faster or slower pace.


Pick up where you left off watching a video.


Jot down information to refer back to at a later time.

Closed Captions

Follow what the trainers are saying with ease.

MP3 Downloads

Listen to videos anytime, anywhere


Files/materials that supplement the video training
Your browser cannot access Virtual Labs
Add training to a playlist
or create a new list
Add to current playlist
or add to an existing list
Add to new playlist