Traveling with Cisco Modeling Labs

On By dustin

For some reason, I decided that I wanted to maintain access to Cisco Modeling Labs (CML) during my travels so that I could stay up to date on my studies. Since my homelab had to be packed up, I decided to take my CML instance with me on my trip. If you don’t need your CML server to have Internet access, you can easily just connect directly to your workstation. However, in my case, I wanted to make sure my system was receiving updates, as well as support labs that needed external access.

This post will quickly walk through my simple travel setup.

What’s needed

Here’s what you’ll need to replicate my setup:

  • Workstation running Fedora (or Ubuntu, etc)
  • CML server
  • USB Ethernet adapter
  • Firewalld enabled
  • Access to modify firwalld

I run CML on a Beelink mini PC. It is small, easy to travel with, and can still run decent simulations. My setup looks like the below:

Network Setup

My CML server directly connects to my workstation, which then acts as a gateway to the Internet for updates or for labs that require external access. Depending on where I’m staying and the Internet options available, the workstation might be connected via a wired connection or WiFi. Most often, its WiFi since I’m usually in hotels or Airbnbs.

To support external access, I have to enable NAT (masquerading) on the workstation for the interface CML uses. Below you can see that I use the nm-shared zone to support masquerading for CML.

Validation

With this setup, my CML can now reach the Internet for licensing checks or security/ application updates for CML itself, or nodes hosted in CML:

Conclusion

I like this setup because it allows me to stay working on small projects despite not having access to my normal lab. It’s small, easy to setup in new places, and helps keep me sharp. Thanks for reading.