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Hi Jeremy

Aren't you going to be busy writing articles for Networkworld? :)

This is a fantastic idea btw. Somebody commented on your blog on how they had setup all a whole bunch of labs on GNS3 previously, and when I asked them where could I download them, I never heard back from them.

Moreover, whenever I seem to use GNS3, I keep getting stuck with 50%-100% CPU usage. I've not really pursued this issue yet, but it would be nice in the course of becoming a Cisco expert, that I'd not have to learn to be a GNS3/Dynamips/DynaGen expert as well.

In any case, 1 thing that would be great to see are all the Network topologies you use in your great CBT Nuggets series for CCENT, CCNA, CCNP and whatever else you have.

Would you be allowed to do that?

Cheers
Shaun

Great idea! I was looking for labs for ccnp.

I just downloaded gns3 after reading your blog the other day, and used the ios from the 'ebay routers' that I bought after your recommendation.

Cheers.

Hi Jeremy,

1. Need a scripting system that resets the labs (router configurations) when someone finishes.

I thought this is pretty easy for this, all you need to do is to stop all the routers in dynamips, delete all the files in the working directory, and start all the routers again. Here you go~!

You might want to look at the Cisco Network Academy BSCI lab guide. You can buy it for something like $30 and it has lots of labs, all using one of two topologies.

Sean

These are all awesome ideas. I know that you can fix the CPU usage issue with the "idle timer" in GNS3 - I haven't played with it yet myself.

I planned on using some of the topologies I've used for CBTNuggets; I was also hoping to put together a topology that mirrored the CCIE Labs book by Cisco press - awesome book for the price.

Jeremy,

I had a similar idea a few months ago but I lost motivation. Maybe I can help you get this started.

Josh

Hi Jeremy.

Switchnet Sverige AB are willing to help with the hosting and the web development needed. We could also provide servers to run labs on. Since all of us are registered instructors of the Cisco Network Academy program I think we could contribute to the project.

Switchnet would provide as much as we can as long as:
We can use this to aid in the further development of our commercial product at http://www.switchlab.se/.
Our logos and links to our websites are placed on the site.
It does not cost us to much and can be handled as a spare-time project.

This is a brilliant idea.

The biggest issue I can see you facing is CPU scaling, GNS3 is designed with each "user" having their own resources (i.e, PC with cpu & memory), with a hosted solution you could be running tens or even hundreds of labs simultaneously funding that kind of backend may be beyond a free solution.

... anyway, apologies for being negative, I love the idea and would offer to help :)

@Eric

But he needs a script, to do this automatically.

JC,

You have some great ideas and challenges too. I have been using dynamips, dynagen, and now GNS3 for some time. Despite the GUI that GNS3 provides to dynamips and pemu, it still has a learning curve associated with it's configuration and use. Then doesn't most every program? I have to wonder what will happen if GNS3 becomes more mainstream? Although, it certainly benefits Cisco to have a large base of people capable of configuring their equipment.

There is one problem to all of this, IOS is licensed. It's up to the user to read the licensing for IOS, I'm not a lawyer. That aside, GNS3 is a great tool, but only one of many that a person needs to begin learning about data networking and Cisco router configuration. It's also the UNDERSTANDING of why a particular model of hardware and version of IOS that is used over another, how it's configured properly for that environment, and how to troubleshoot and fix any problems that will weed out those people who ar great and those that truly want to learn. A network admin/engineer needs to know how to use their computer too. How many times have I read on the forums, or in blog responses, where someone can't create a loopback or tap interface, or change the their OS network settings? Even how to use ping, trace route, and the multitude of other programs needed to configure and maintain a computer network. Can you say "google"?

Also, a real piece of equipment requires that you work with the physical layer and cable it properly, maybe even fabricate some patch cables or a rollover cable. [god forbid!] It's this inconvenience from which many of us have gained our experience.

As you mentioned, people need to understand why they're creating a particular lab configuration and this requires a greater understanding of networking than the ability to just power on a router. A good start would be to have lab descriptions that include a real world association, e.g. this two router serial link is your brand office to main office connection; and include a diagram.

Anyway, http://www.blindhog.net/category/gns3/ has some great GNS3 labs with videos to show you how to configure the labs to get a person started. With a video it can't get much easier than that. And a must have resource for labs and GNS3 help can be found on the hacki forums at http://7200emu.hacki.at/. And the Cisco certification labs books are a great resource too. Oh, I think the public library is still free.

Great idea! But I think that you need to be very careful with the IOS security, I don't ever used GNS3 before but can you do something like "copy flash:image.bin tftp"?. Also what about legal issues when using IOS in such a way?

@MT

I'd definitely have to block TFTP (and other methods of transferring off the IOS) at the firewall. As for the legal IOS issues...now there's a good question. Don't know.

@Nick - no worries! Those are all things I'd have to figure out.

Hi Jeremy,

Just developing lab scenarios is a great idea in its own right even without providing access to GNS on a hosting machine, as many people can run it locally on their machines.

Very good idea!

I actually have been thinking the same idea. Ehm :-)

1. It needs a good processing pc box that can run several dynamips instances
2. It needs a scheduling system which relates with #1

David, any quad core CPU box should be fine :)

Hey Jeremy,

There are some very good opinions here. I love the idea of a hosted GNS3 service, but there is a pretty high barrier of entry to get it to a point where it scalable for the many users that will benefit. How about, like Abdu suggested, developing the lab scenarios on the domain you purchased. It will immediately be a benefit to all. I for one would be excited for helping in any way possible (unfortunately I'm not a web developer :(, but I have played around in both Drupal and Joomla.

I'm sure we'll see this thing take a life all it's own, especially if the goal is to build a GNS3 hosted lab environment.

Alright - my main thought is SIMPLIFY.

I like Abdu's idea - just providing some labs will be valuable in their own right. I'll start by building some CCNA level labs & GNS3 topologies, see what ya'll think, and keep moving up the cert line as I go.

Josh H - I may be looking for your help! You've definitely got a massive GNS3 foundation already.

I'll probably start just by building a Joomla-based site (if I can figure out how to work Joomla) that has some simple pages where I (and others) can easily post labs). I'll worry about getting the hosted GNS3 solution later.

Joomla, GNS3 solution...
what about that cisco forum ? ;)

Or maybe make that forum with a sub-forum for your gns3 labs..

I've tried using GNS3 but have had no success running it. I've spent the past two hours trying to get it to work with no success. Please help me!

Here is what I did:

1. I installed GNS3
2. I launched the Dynamips Server command prompt file
3. I went into GNS3 and added my Cisco 2600's IOS
4. I dragged the Cisco 2600 router into the white background and I right-clicked the router and clicked start. The light of the router turned green so it turned on.
5. I right-clicked the router and clicked console, but then it says "file not found".

What am I doing wrong? If anyone knows please help. Thank you.

This is a really good idea. However, i do think you will be up against it when it comes to raw processing power. Three or Four router labs will be fine, but larger topologies will need plenty of grunt. Do you have any thoughts on server specs?

Good idea, Jeremy. You can setup the environment on one or multiple Amazon EC2 instances. It's cheap and powerful. The only problem I see is the licencing problem of the IOS images...

Great idea. GNS3 cant get any easier. For all with the CPU spiking issues. In the latest version of GNS3 (GNS3 0.4.1) you can use the UI to set the idle pc value without passing any commands to dynamips console.

I am waiting for the late April release where they are going to implement the virtual host feature to ping, tracer route etc. the routers.

Jeremy forget hosting GNS3 itself. I mean anyone can install that app locally. Just make some GNS3 labs and watch people love it crazy. Heck I know I would even pay for some GNS3 labs.

What sucks is their isnt any real Cisco Switch support on GNS3.

Jeremy,

I've been playing with GNS3/Dynagen for some time, but GNS is still not error free, especially if you add many routers to the topology, so Dynagen would be a better solution for complex topologies (and believe me it is not hard at all to play with it).
I'm not sure that you will be able to have a server that would support many concurrent dynamips sessions, but a site that contains only topologies and maybe router configuration files would be excellent. In this case you won't have to deal with IOS issues. Anyone could just download the topology and config files into his computer and run his own instance of GNS3/Dynagen session...

There is a todo list for GNS3:
http://code.gns3.net/gns3-devel/raw-file/tip/TODO

"* A standalone server to automatically configure GNS3 clients in order to use remote hypervisors (intended for learning environments, schools/universities, where IOS image cannot be distributed)"

Now, I think that is what you looking for.
(btw, GNS3 0.5 is released)

There is a todo list for GNS3:
http://code.gns3.net/gns3-devel/raw-file/tip/TODO

"* A standalone server to automatically configure GNS3 clients in order to use remote hypervisors (intended for learning environments, schools/universities, where IOS image cannot be distributed)"

Now, I think that is what you looking for.
(btw, GNS3 0.5 is released)