If someone asks me which tool I enjoy using most, the answer comes without hesitation: EVE-NG. It is the playground where I build, break and understand networks — without anyone calling because production is down.

What EVE-NG is

EVE-NG (Emulated Virtual Environment – Next Generation) is a network emulation platform. Put simply: a program in which I click together whole networks from real device images. I drag routers, switches, firewalls and servers onto a canvas, connect them with virtual cables and boot them — and they behave like the real hardware, because they run the very same operating systems inside.

And it does so across vendors:

  • Cisco in all its flavours — IOS, IOS XE, NX-OS, IOL
  • Arista, Juniper and other router and switch platforms
  • Firewalls from Fortinet, Palo Alto and others
  • plus Linux and Windows servers or Docker containers as endpoints

Multi-vendor in a single topology — exactly what real environments throw together, and something you could otherwise only reproduce with a cabinet full of expensive hardware.

It all runs in the browser

No heavy client, no installation on your workstation. EVE-NG runs on a server or in a VM, I open it in the browser and work directly on the device consoles. A lab is, in the end, a file: I can save it, hand it over, and next time pick up exactly where I left off.

What I use it for

The most important case is everyday work: testing changes before they go into production. A new routing design, a firewall rule, the behaviour of a particular firmware — I rebuild it in the lab and keep trying until I understand why it works, or why it doesn't.

Then there is the calm learning: watching a protocol at work, deliberately provoking a BGP problem, preparing for a certification. And reproducing faults — when something looks odd in production, I recreate the situation in the lab and take it apart without any time pressure.

Why it thrills me

Because it takes the fear out of the work. In the lab I'm allowed to break everything — a wrong command doesn't take down a real link, only a virtual one that is back up two clicks later. That freedom changes how you learn: you try more, you reach for things you'd never risk on production hardware, and in the end you understand not just that something works, but why.

That is exactly why EVE-NG is not merely a tool for me, but the place where I learn the most about networks. Honestly: I think it's brilliant — and it probably shows.