The scoop on CML and VIRL!

It’s always nice on a wet British morning when the sky looks grey and drab and you don’t want to get out of bed to have something to counterbalance the crap UK weather.

Firstly one of my sons woke up at 5:40am, usually this would mean the start to my day, but one quick nappy change later and he was back in his bed fast asleep, they then woke up at a very respectable 7:30 allowing the wife and I to get a rare lie-in together.

The second was getting a message from Craig at Cisco. He picked up on a post that I made on some information on CML (Cisco Modeling Lab) and offered “to clear up people’s questions and misinformation”. Clearly there are a lot of people wanting to hear more about CML, and more importantly, to start having some real hands on experience of it, so I wasn’t going to pass up the chance to quiz him, and having him clarify what we know (or what we think we know) would certainly be a good idea.

Over the last few months we have heard a lot of supposed “fact” about CML, how it is what used to be code named VIRL, and quite frankly, there is probably more wrong information out there than truth.

So with coffee in hand I sent him a few questions through Google+, and he got back to me on email.

I am pasting things in context of my questions to him. My questions are in bold, Craig’s replies are in blue. We’ll start with Craig’s introduction so you can get an understanding of who he is in relation to CML.

Hi Craig, thanks for getting in touch. I have a few questons about CML, and then would love to hear anything else you’d like to add.

In terms of introductions, I am the Cisco Technical Marketing Engineer for Cisco Modeling Labs, and you can reference these answers. I represent CML within the organization called Learning@Cisco (L@C) who will be launching CML which is based on VIRL. There are other organizations such as the Innovate team and the OnePk team who also use VIRL
CML is built for the Corporate users that are looking to validate
VIRL will be available via Devnet and will be free for any registered user to download. This will be a community-supported platform. For more information on ‘Devnet’, please take a look at More information on VIRL will be posted there soon. Target FCS is 7/30
People ask what’s the difference between VIRL and CML? L@C collaborated with the Innovation team (the developers of VIRL) to productize it, run the full test regime so that it’s stable, document, and provide TAC support.
VIRL will be available in other formats, available to customers, but not with the testing regime, TAC supported version, docs, and so on.

I started my studies (as most do) with my head deep into Packet Tracer, will CML replace Packet Tracer?

I haven’t had a conversation about what the story and to be honest, I haven’t compared to two products yet – but will put that on my to-do list

Cisco are very evidently embracing the open networking technologies that are emerging, so will CML link into the ONE (onePK) suite?

For onePk, you can install the OnePk All-in-one OVA today and the CML OVA and they will communicate. Also, I installed the OnePK API directly in the CML server and that works too

What is the estimated release date for the “consumer” version? I have heard from different sources that it will be available through DevNet for free, or that it will be sub $100, is this the case?

Answered above in Craig’s introduction.

Will CML have a new logo?

This is the CML logo

Does CML support DMVPN?

Not at this time.

Will CML (at some stage) have more support for layer 2? Clearly these functions are more ASIC driven, but as the CCIE requires the ability to do spanning-tree this is something that people will be looking for

Yes, we are building a Layer 2 image now and working around some of the ASIC issues.

Speaking of the CCIE, Cisco have said that the lab will be 100% virtualized, is CML going to be the back-end for the new exam?

Yes, CML will be the backend for L@C CCIE labs, in the future. (L@C runs the CCIE labs so that’s the correlation)

CML supports connections to real equipment, which will probably overcome the layer 2 issue, does this mean that (in time) we would be able to join CML and GNS3 networks?

CML does have external connections for both L2 and L3 so you can connect to external devices or other virtual images

Will CML allow us (again in time) to run other vendors equipment within it?

 In the first release you can run any image that runs within OpenStack, Cisco image or other.
So there you go, some concrete information from Cisco!

sh brief

In short:

  • CML and VIRL are actually separate
  • VIRL will be free, and out soon (end of July by the looks of it)
  • VIRL will be community supported, CML will  have full Cisco support (TAC, documentation etc)
  • Integration with ONE (onePK) will be possible (how cool is that?!)
  • There will be ASIC support! (in time)
  • It will connect to GNS3!
  • It will run OpenStack images (Ubuntu, RedHat variants, SuSe)
Keep watch on the DevNet site and keep your eyes open around the end of July for VIRL.
I would like to express my thanks to Craig for taking the time out to answer the questions, and to clear up the confusion surrounding CML and VIRL.


  1. Ufuk Eskici May 30, 2014
  2. Anonymous June 4, 2014