This article explains how to install Cisco Modeling Labs free version. Learn how Network as Code (NaC) is used to import and share Cisco labs based on a YAML-generated text file. This makes sharing labs much easier than with large GNS3 or EVE-NG binary files.
Disable Microsoft Hyper-V
VMware Workstation and Microsoft Hyper-V are not compatible on Windows Home Edition or Windows Pro. You will get a nested virtualization not supported error when starting CML with VMware. Nested virtualization enables Cisco IOS devices to run as separate VMs within CML VM.
Hyper-V is a Type 1 hypervisor that exclusively manages all hardware virtualization and prevents CML from using nested virtualization with VMware. The same problem will occur when using GNS3 and EVE-NG with VMware. This automation lab setup was tested with VMware Workstation 17.5 installed on Windows 11 Home and Windows 11 Pro. There are separate instructions included for both operating systems.
Disable Hyper-V (Windows Home Edition)
There is only partial support for Hyper-V included with Windows Home Edition. This makes it easier to disable Hyper-V and allow nested virtualization required with CML.
Start Windows PowerShell as Administrator and type the following command to disable Hyper-V launch from Windows. Hint: If you don’t know how to start Windows PowerShell as Administrator ask ChatGPT.
bcdedit /set hypervisorlaunchtype off
Uncheck the following features to disable Hyper-V components in Control Panel and then restart your computer:
Control Panel -> Select Programs -> Select Turn Windows Features on or off
1. Uncheck Virtual Machine Platform
2. Uncheck Windows Hypervisor Platform
3. Uncheck Windows Subsystem For Linux
Memory Integrity Setting:
Type core isolation in Windows search bar, select core isolation, and turn Memory Integrity setting OFF. You will have to restart your computer then continue with lab setup.
Disable Hyper-V (Windows Pro)
This article explains how to fully disable Hyper-V on a machine with Windows Pro. Hyper-V is fully supported with Windows Pro and this makes it more complex to disable all Hyper-V components. ChatGPT can provide instructions on how to reinstall Hyper-V software at a later date when VMware is uninstalled.
Install VMware Workstation
Start with VMware Workstation install using the default settings. Skip this step if VMware Workstation 17+ is already installed and proceed to CML install.
- Go to support.broadcom.com and log in (or register a free account with valid email)
- In the top-right corner, select “Support Portal”, then:
- Choose the VMware Cloud Foundation division.
- Click My Downloads.
- Search for “Workstation Pro”.
- Click on the product and choose the “Personal Use” (same binaries).
- Be sure to check the “I agree to the Terms and Conditions” box – it unlocks the download
- Choose the latest version (e.g., Workstation Pro 17.5.2+ or newer).
- Download and install VMware
- DO NOT install Windows Hypervisor Platform (WHP) option (leave it unchecked).
- On launch, select “Personal Use” if prompted — no license key needed.
Install Cisco Modeling Labs (CML-Free)
Cisco Modeling Labs includes a free tier version with 5-node limit. Learn how to create and test automation scripts on real Cisco IOS. The is preferrable to emulated lab environments such as GNS3 and EVE-NG that are error prone and more complex to setup similar labs. You can also upgrade to CML Personal and use it for real lab testing at work and certification study. Share labs with a YAML text file instead of large binary project files used by GNS3 and EVE-NG.
- Create and test automation scripts on Cisco approved IOS.
- Less complex to setup than GNS3 or EVE-NG that are error prone.
- Share labs with a YAML text file instead of large binary projects.
- Upgrade to CML Personal for additional nodes.
This section explains how to install Cisco Modeling Labs (v2.8) to VMware Workstation and import a lab-ready (Network as Code) topology.
Download CML files from Cisco
Step 1: You will need to first register for a Cisco CCO account. Skip this step if you already have an existing account.
Step 2: Navigate to the CML-Free Sign-up page to register for access to CML-Free.
https://mkto.cisco.com/cml-free.html
Step 3: Navigate to Cisco Software Download and login with your Cisco CCO account.
https://software.cisco.com/download/home
Step 4: Select Modeling Labs on right side-bar and then select CML-Free 2.8 release. The following CML files are for VMware and have been tested with CML 2.8 stable version.
Download CML 2.8.0 server software = cml2_2.8.0-6_amd64-32.ova
Download CML IOS reference platform (images) = refplat-20241016-fcs-iso.zip
Configure CML virtual machine
Step 5: Navigate to your Windows download directory. Close any existing VPN connection.
Step 6: Extract refplat-20241016-freetier-iso.zip to a folder for install.
Step 7: Right-click on cml2_f_2.8.1-14_amd64-35.ova and select Open with VMware Workstation.
Step 8: Follow prompts in the VMware Import Wizard.
Select VMware for personal use
Name for new virtual machine: CML
Storage path: default and select Import
Step 9: CML Virtual Machine settings will open (Do NOT start VM).
Step 10: Verify the following options are set accordingly.
Number of processors = 4
Number of cores per processor = 1
Check Virtualize Intel VT-x/EPT or AMD-V/RVI
Memory: 8GB or more (recommended)
Hard Disk: Expand disk capacity to 100 GB minimum recommended and ignore message. The disk size will automatically resize when virtual machine is started. This is a maximum size only with thin provisioning that assigns disk space based on usage.
CD/DVD: Check the ‘use ISO image file’ check box. Browse to your downloads directory and open refplat-20241016-freetier-iso folder. Select refplat-20241016-freetier file.
Check the ‘Connect at power on‘ check box.
Network Adapter: Select NAT
Step 11: Power on virtual machine and accept EULA (use arrow and tab keys).
CML application setup
Step 12: Confirm standalone all-in-one deployment.
Step 13: Enter system unique hostname: cml-controller (default)
Step 14: Create sysadmin account and assign password. Select yes to ignore password warnings.
Step 15: Create user admin account and assign password to access CML labs via Web UI. Select yes to ignore password warnings.
Step 16: Select continue for DHCP (default) to configure IPv4 addressing from VMware. This only applies to external connections such as the internet or Inter-VM links.
Step 17: Confirm settings. CML will start copying refplat images at this point for Cisco devices. This could take several minutes to copy images based on your laptop speed. Select Continue button and wait for CML server to reset.
*Cisco CML official online documentation
Download Cisco configuration lab (network as code)
Step 18: Click on link to download this lab topology for import to CML. This is a text file approximately 30KB size that provides configured devices as shown.
Step 19: Access CML UI from your browser with DHCP assigned IP address shown in the CML VM console (ignore 9090). Select Advanced button to ignore any SSL certificate warnings, and select Proceed.
This command is an example with CML default username admin and password you created when installing CML. The assigned IP address is an example only and could be different.
https://192.168.216.129
Username: admin
Password: **********
Step 20: Select Import and browse to your downloads directory. Select lab ready topology student_lab.yaml and import into CML. Your browser could randomly disconnect from CML server when there is inactivity. Click your browser reload button to refresh web page only if this occurs.
Step 21: Select Start Lab and wait a minute for lab topology to initialize. This only occurs once when importing a new Cisco lab and sometimes will require starting an individual network device/s with right-click start lab option.
Step 22: Console and create SSH key on each Cisco device since they are not imported automatically. Press enter key to accept the default 2048 bit key length.
device>enable
Password: cisco
device(config)#crypto key generate rsa
Choose the size of the key modulus. How many bits in the modulus (2048): Enter
Save the running configuration to startup configuration on each device.
device#copy run start