GNS3 vs EVE-NG: Which One Should You Use in 2025?

Let me guess: you’re trying to decide between GNS3 vs EVE-NG for your network simulation needs.

You’ve heard about GNS3. You’ve heard about EVE-NG.

Maybe you’ve even used Packet Tracer.

And now you’re wondering — which one is right for me?

That’s a good question. But it’s not just a technical one.

It’s about how you want to learn, how far you want to go, and how much time you’re willing to invest in doing it right.

The GNS3 vs EVE-NG debate has been around for years.

But 2025 is different.

Both tools have evolved.

So have the certifications, the job market, and what employers expect from network engineers.

So in this article, we’re going to give it to you straight:

• What makes GNS3 and EVE-NG different?
• Which one is better for CCNA, CCNP, or CCIE practice?
• How do they compare on setup, performance, cost, and realism?
• What about Cisco’s own tool (CML)?
• And yes — we’ll talk about Packet Tracer, too (because a lot of people reading this are still beginners, and that’s okay).

By the end, you’ll know which platform fits you — based on where you are and where you’re headed.

This isn’t a promo.

This is what we’ve learned from thousands of hours training engineers at all levels — inside Dynamips and beyond.

Let’s get into it.

Simulation vs. Emulation — And Why It Matters More Than You Think

Before we talk about GNS3 vs EVE-NG, there’s one thing we need to clear up:

These two tools don’t even belong in the same category as something like Packet Tracer.
Why? Because they don’t simulate — they emulate.

Let’s break this down, without the tech jargon.

Simulation (like Packet Tracer or NetSim)

Simulation tools try to mimic how devices work — but without running the actual operating system (like IOS or ASA).

They’re great for:

• Learning concepts
• Practicing basic CLI
• Lightweight, fast labs that run on any laptop

But they fall short when:

• You need to test complex features
• You want to troubleshoot real behavior
• You’re preparing for CCNP, CCIE, or live environments

Examples: Cisco Packet Tracer, Boson NetSim

Emulation (like GNS3 and EVE-NG)

Emulators run the real OS inside a virtualized environment.

This means:

• Real boot-up processes
• Actual device behavior (with bugs and all)
• True-to-life configurations and testing

Examples: GNS3, EVE-NG, Cisco Modeling Labs (CML)

So when you compare GNS3 vs EVE-NG, you’re comparing two emulators — not simulators.

But Why Does It Matter?

Here’s the truth most people don’t say out loud:

If you’re serious about networking — especially beyond CCNA — you need emulation.

You wouldn’t train for a pilot’s license on a cartoon flight simulator.

You’d want something that flies like the real thing.

It’s the same here.

Want to understand why Packet Tracer, while useful, eventually holds you back?
Read this: Is Packet Tracer Good Enough for CCNA?

The Real Reason Some Instructors Still Use Simulation

(And Why They Hope You Don’t Ask Too Many Questions)

Let’s get real for a second.

If emulation tools like EVE-NG and GNS3 are more powerful, more realistic, and better for real-world prep…

Why are some instructors still using Packet Tracer and NetSim in 2025?

Here’s what no one tells you:

It’s not because simulation is better.

It’s because it’s easier — for them.

The uncomfortable truth:

Simulation tools make teaching feel smooth.

No setup issues. No licensing headaches. No need to explain what to do when the image won’t boot.

Everything works on the first try.

Everything looks clean.

But here’s the problem:

That’s not how real networking works.

In real life, devices don’t always cooperate.

Configs behave differently under load.

Sometimes the only way to learn is to troubleshoot for hours — and figure it out the hard way.

And guess what?

Simulation tools can’t teach you that — because they’re not real.

So why do some instructors avoid EVE-NG or GNS3?

Because emulation introduces mess.

And mess = questions.

And questions take time to answer.

But you?

You’re not here to memorize the config for HSRP.

You’re here to learn how real networks behave when the pressure is on.

And for that, you need tools that don’t pretend.

Want to stand out in interviews, client meetings, and high-stakes outages?
Stop using tools designed to “look clean.” Start using the ones that act real.

GNS3 in 2025: Still Viable — But Slowly Falling Behind

If you’ve been in networking for a while, you probably started with GNS3.

So did a lot of us.

Back in the day, it was a game-changer.

You could emulate real Cisco devices on your own machine — no rack, no hardware. Just a laptop, some images, and a bit of stubbornness.

And honestly? That was enough for a long time.

But here’s the thing:

GNS3 hasn’t really kept up.

It still works.

It’s still useful for small topologies.

But if you’ve tried running a full-scale lab in GNS3 recently — especially something like SD-WAN or multi-router redistribution scenarios — you’ve probably hit some walls.

GNS3’s Strengths (Still Worth Mentioning)

• ✅ It’s free
• ✅ Lightweight for basic labs
• ✅ Good community support (though not as active as before)
• ✅ Great if you’re working with older IOS images or legacy tech

Where GNS3 Falls Short Today

• ❌ Not built for multi-vendor or advanced enterprise labs
• ❌ GUI-based project management gets messy fast
• ❌ Poor support for cloud or remote access setups
• ❌ Installing it properly in 2025 is still a mini nightmare
• ❌ No native SD-WAN or automation-focused support

And let’s be honest — it feels a bit outdated.

If you’re preparing for CCNP or CCIE, or working in modern production environments, you’ll outgrow GNS3 faster than you think.

The GNS3 Trap

A lot of engineers stick with it just because it’s what they know.

And hey — there’s nothing wrong with using familiar tools.

But if your goal is to move forward in your career, sometimes you have to let go of what used to work, and step into what’s working now.

GNS3 was a pioneer.

But in 2025, it’s not the best tool for serious training anymore.

EVE-NG in 2025: Why It Became the Gold Standard

There’s a reason why most advanced engineers — especially those prepping for CCNP, CCIE, or working in real-world enterprise networks — have moved to EVE-NG.

It’s not hype.

It’s not marketing.

It’s just better where it matters.

Built for Engineers, Not Just Enthusiasts

EVE-NG doesn’t hold your hand.

It doesn’t pretend to be pretty.

It just works — and lets you build, break, and troubleshoot real environments.

And that’s exactly what you need if you’re serious about networking.

Why EVE-NG Outshines GNS3 (Especially in 2025)

• ✅ Runs like a real enterprise lab
• ✅ Multi-vendor support — Cisco, Fortinet, Palo Alto, Linux, you name it
• ✅ Great for CCNP/CCIE-level labs (routing, switching, SD-WAN, automation…)
• ✅ Remote access ready — build it on a rented server and access from anywhere
• ✅ Web-based interface — clean, flexible, and scalable
• ✅ Blueprint-aligned — especially if you use lab packs like ours

Cloud-Friendly by Design

GNS3 still wants to live on your machine.

EVE-NG? It’s perfectly happy in the cloud — which means:

• You don’t have to burn your laptop with every lab
• You can switch between devices, locations, and users
• Your labs are always on, always ready

Used by Pros, for Pro-Level Practice

We’ve seen hundreds of engineers move from GNS3 to EVE-NG once they realize what’s possible:

• Running 20+ devices in a lab? ✅
• Testing failover between data centers? ✅
• Simulating multi-site SD-WAN? ✅
• Preparing for the CCIE lab? Definitely ✅

TL;DR?
GNS3 is where many engineers start.
EVE-NG is where they grow.

What About Cisco CML? Great on Paper — But Limited in Practice

Let’s be honest — anything with the word “Cisco” in it gets attention from network engineers.

So naturally, when people hear about Cisco Modeling Labs (CML), they think:

“Well, it’s made by Cisco. It must be the most accurate tool for certification prep.”

But here’s what you should know before jumping in:

CML Is a Simulator and an Emulator — But Mostly for Cisco

CML does some things well:

• ✅ Comes with official Cisco images (no licensing hustle)
• ✅ Clean GUI with drag-and-drop interface
• ✅ Easy to get started with simple labs
• ✅ Good for learning routing, switching, basic designs

But it has some real limitations too:

Where CML Falls Short

• ❌ Vendor-locked — it’s Cisco-only. No Palo Alto. No Fortinet. No Linux boxes.
• ❌ Limited image flexibility — you’re stuck with what Cisco gives you
• ❌ Performance isn’t great with large topologies
• ❌ No real community ecosystem like EVE-NG or GNS3
• ❌ Expensive for what it offers (especially if you’re not using it in a corporate environment)

Speaking of Cost…

• Cisco CML Personal License (for individual users): ~$199–349 per year
• Compare that to:
  • EVE-NG Community Edition: Free
  • EVE-NG Pro (lifetime license): ~$173 (1 Year License

So yeah — you’re paying more for less flexibility.

Our Take?

If you’re just getting started and want a clean Cisco-only lab, CML can work.

But if you’re preparing for real-world networks — or even CCNP/CCIE where you need to mix vendors, break things, and go deep —
you’ll outgrow CML fast.

TL;DR:
CML is fine for small, simple, Cisco-only labs.
But EVE-NG gives you way more room to grow — for less money, and fewer limits.

What About PNETLab? Good Idea, Bad Execution

PNETLab showed up a few years ago as a kind of remix of EVE-NG.

At first glance, it looked promising:

• Free to use
• Web interface
• Familiar layout for anyone who’s used EVE-NG
• Even a few pre-installed images in some builds

But here’s the real story…

The Harsh Reality of PNETLab

• ❌ Development has stalled — no major updates, no bug fixes, no roadmap
• ❌ No real support or community
• ❌ Frequent issues with image compatibility
• ❌ Security concerns (no transparency on patches or improvements)

What started as an exciting open-source alternative has slowly turned into an abandoned side project.

Should You Use It?

If you’re just trying to run a few basic labs and don’t mind unstable software — sure, you can install PNETLab.

But if you’re investing serious time into becoming a better engineer?

Don’t waste it on tools that aren’t being maintained.

Better Alternatives Exist

• Want a free solution? Use EVE-NG Community Edition — still actively maintained
• Want something stable and scalable? EVE-NG Pro is worth every cent
• Want Cisco-only labs with official images? Try CML (but know its limits)

Bottom line?
PNETLab had potential. But in 2025, it’s just not worth your time.

Hardware Requirements: What You Need to Run GNS3, EVE-NG, and CML Smoothly

Let’s say you’ve picked a tool.

Now comes the next big question:

“Can my laptop even handle this thing?”

Because whether you’re running GNS3, EVE-NG, or Cisco CML — these tools are emulating real network operating systems.

That means they eat RAM, CPU, and disk space like snacks.

Let’s break down what you really need — based on real-world use, not ideal marketing claims.

GNS3: Light… Until It Isn’t

GNS3 starts off easy. A few routers here, a switch there — no big deal.

But the second you add:

• Firewalls
• Layer 3 switching
• 5+ routers in a topology…

…your machine starts sounding like it’s about to take off.

Minimum:

• 8 GB RAM (bare minimum)
• 4-core CPU
• SSD (you will regret using HDD)
• GNS3 VM installed with VirtualBox or VMware

Recommended for real labs:

• 16 GB RAM
• i7 or Ryzen 5 (or better)
• Run the GNS3 VM externally (not on the same host OS)

EVE-NG: Built for Power Labs

EVE-NG doesn’t mess around.

It assumes you want to run serious topologies — and it’s designed for scale.

Minimum for basic labs (CCNA-level):

• 8 GB RAM
• 4 vCPU
• SSD storage
• Bare-metal install or small VMware VM

Recommended for CCNP/CCIE-level labs:

• 16–32 GB RAM
• 6–8 vCPU
• 100+ GB SSD
• Remote/cloud server if running large topologies

Good news?

You can install EVE-NG on a cloud server and access it from your browser — no stress on your own laptop.

We even offer a version preloaded with images and labs:
Try the EVE-NG Full Pack

Cisco CML: Moderate Demands, Limited Flexibility

Cisco CML is middle of the road — not too heavy, but also not designed for massive scale.

Minimum:

• 8 GB RAM
• 4-core CPU
• VMware ESXi, Fusion, or Player

Recommended:

• 16 GB RAM
• SSD
• Expect limitations if you run more than 10–12 devices in a lab

Pro Tip: Rent a Cloud Server

Don’t want to upgrade your machine?

Rent a VPS or dedicated server.
Install EVE-NG once, access it from anywhere.
No fan noise. No overheating. No problem.

Bottom line?
If you’re doing more than basic CCNA labs, don’t cheap out on hardware.
Emulation gives you real learning — and that takes real resources.

Cost Comparison: What Do GNS3, EVE-NG, and CML Actually Cost You?

Let’s be real — your time and budget matter just as much as the tool itself.

So here’s a clear breakdown of what each platform costs (and what you’re really paying for).

GNS3 – Free (But Not Effortless)

• ✅ Software: Free
• ✅ Community support: Free
• ❌ Cisco images: Not included (you’ll have to find them yourself)
• ❌ No native support for modern technologies like SD-WAN or automation

The real cost?

Time, setup frustration, and limited scalability for larger topologies.

EVE-NG – Free or Paid, Your Choice

• ✅ Community Edition: Free and surprisingly powerful
• ✅ Pro Edition: ~$173 (1 Year License – unlocks all Pro features and two active concurrent Administrator accounts sessions.)
• ✅ Full-featured web interface, multi-vendor support, and CLI realism
• ❌ Cisco images not included by default (though available via third-party packs)

The smart option:

Start with the free version — and upgrade to Pro only if you want more features or easier UX.

Want everything set up and ready to go?
Check out our EVE-NG Full Pack

Cisco CML – Pay for the Badge

• No free tier
• Personal License: ~$199–349 per year
• Includes official Cisco images
• Vendor-locked (no Fortinet, Linux, Palo Alto, etc.)
• Limited scalability and community compared to EVE-NG

Verdict?
You pay more — and get less flexibility in return.

Cost & Feature Comparison

So, What Should You Pick?

• Tight budget? → Start with EVE-NG Community.
• Ready to commit? → EVE-NG Pro is a one-time, high-value investment.
• Need Cisco-only images with official support? → CML will do — but comes with limits.
• Want the nostalgia? → GNS3 is still around… but not aging well.

Pro tip: The money you save on free tools will cost you in time — unless you use them right.

EVE-NG Editions: Free vs Pro — And Why You Might Not Need to Pay

Let’s get one thing straight:

You don’t need the Pro version of EVE-NG to become a serious network engineer.

In fact, the free version — a.k.a. EVE-NG Community Edition — is powerful enough for:

• Full CCNA and CCNP lab environments
• Most CCIE Enterprise tasks
• Realistic CLI training with multi-vendor topologies
• SD-WAN, BGP, OSPF, VLANs, firewalls — you name it

What You Get with EVE-NG Community Edition (for $0)

• ✅ Unlimited labs
• ✅ Full CLI interaction
• ✅ Multi-vendor support (Cisco, Fortinet, Palo Alto, etc.)
• ✅ Node types: routers, switches, firewalls, Linux VMs
• ✅ All blueprint topics up to CCIE-level

If you’re resourceful and don’t mind a slightly less polished UI, you can go a long way without spending a dime.

What You Get with EVE-NG Pro

• Native Docker and Windows support
• Smart features like drag-and-drop topology editing
• Multi-user support (great for teams, less useful for individuals)
• Better file and image management

Is it better? Yeah, in some ways.

Is it necessary? Not for most solo learners.

So… Should You Go Pro?

Here’s how I usually break it down for students:

Our Advice at Dynamips?

Start with EVE-NG Community Edition.

Get your hands dirty.

Build labs. Break stuff. Learn how devices behave for real.

And if one day you feel limited — then (and only then) go Pro.

You can always scale up.

But what matters most?

You start.

GNS3 vs EVE-NG: Which One Should You Use Based on Your Goals?

There’s no one-size-fits-all answer — but there is a right answer for you.

Let’s break it down by common scenarios.

“I’m just starting out with CCNA.”

Use: Packet Tracer (to get started), then move to EVE-NG

Why?

Packet Tracer is lightweight and beginner-friendly. But once you start practicing real CLI, you’ll need EVE-NG — even the free version is perfect for this stage.

Not sure why? Read:
Is Packet Tracer Good Enough for CCNA?

“I’m preparing for the CCNP.”

Use: EVE-NG Community or Pro

Why?

You need full routing protocols, real images, and realistic topologies. GNS3 struggles with scale and realism at this level.

“I’m aiming for the CCIE.”

Use: EVE-NG (ideally Pro or cloud-hosted)

Why?

At this level, you need to simulate large environments, multiple technologies, and real-life failure scenarios. GNS3 and CML just can’t keep up.

“I’m into automation, scripting, or DevNet.”

Use: EVE-NG Pro or CML

Why?

Docker support, API access, and programmable lab environments work better in Pro or CML. But again — CML is vendor-locked. EVE-NG gives you more flexibility.

“I’m a trainer / I want to share labs with others.”

Use: EVE-NG Pro

Why?

Pro lets you set up multi-user environments, manage permissions, and share labs — clean and simple.

“I just want to practice small labs on my own laptop.”

Use: GNS3 or EVE-NG Community

Why?

If you’re not building massive topologies and just need a CLI playground, both will work. But EVE-NG gives you more room to grow when you’re ready.

Summary Table

Final rule?
Don’t pick a tool based on nostalgia or popularity.
Pick based on what will make you better.

Final Thoughts: What We Use at Dynamips (And Why)

We’ve tested everything.

GNS3. CML. Even PNETLab back when it showed promise.

And after thousands of hours building labs and helping engineers prepare for real-world roles and certifications…

We chose EVE-NG.
And we haven’t looked back.

Why?

Because it scales.

Because it feels real.

Because it gives our students the closest thing to a live network — without touching a physical device.

Want to Skip the Setup and Start Practicing Today?

If you’re tired of downloading images, troubleshooting installs, and wasting your evenings fixing your lab instead of learning…

We’ve built something for you.

Click here to get started with the EVE-NG Full Pack

…and start training like a real engineer.

No setup. No stress. Just practice — right away.