Cisco Modeling Labs Free gives you real IOS images at no cost. The catch: a maximum of 5 simultaneous nodes. That limit hits faster than you think.
Why 5 Nodes Isn't Enough
A basic OSPF multi-area lab needs:
- 3 routers (backbone + 2 areas)
- 2 switches
- 2 PCs for testing
That's 7 nodes — already over the limit.
A simple enterprise topology with redundancy? 4 routers, 4 switches, 2 hosts = 10 nodes. Double the limit.
Even CCNA study labs regularly exceed 5 nodes. CML Free works for the most basic single-protocol exercises, but anything resembling a real network won't fit.
Unmanaged switches and external connectors don't count against the limit. You can use them to extend slightly — but they don't run IOS, so they can't participate in STP, VTP, or port security labs.
Your Options
Option 1: Pay for CML Personal ($199/year)
CML Personal raises the limit to 20 nodes — enough for most certification labs. You also get NX-OS, ASAv, and additional Linux images.
The trade-off:
- $199/year recurring cost
- Still Cisco-only — no Juniper, Arista, Nokia, or Palo Alto
- Still requires a VM with nested virtualization
- 20-node limit can still be restrictive for enterprise-scale labs
Option 2: Use GNS3 or EVE-NG (Free, No Node Limits)
Both tools are free with no node limits. They support multi-vendor images.
The trade-off:
- GNS3: 4-8+ hours for first-time setup (VM, image sourcing, troubleshooting)
- EVE-NG: requires a dedicated server (1-2 days to set up)
- You source and manage device images yourself
- Every lab built manually from scratch
Option 3: Use ContainerLab (Free, Container-Based)
ContainerLab runs network operating systems as Docker containers. No node limits, fast deployment, and infrastructure-as-code approach.
The trade-off:
- Requires Docker + Linux host
- Most device images must be sourced and built yourself
- YAML topology files + manual device configs
- Not beginner-friendly
Option 4: Use NetPilot (AI-Powered, No Limits)
NetPilot runs cloud-hosted ContainerLab with AI that generates your topology and configs automatically.
What you get:
- No node limits on any tier
- Multi-vendor: Cisco IOL, Nokia SR Linux, Arista cEOS, Juniper cRPD, Palo Alto, Fortinet, FRR
- AI generates complete labs from plain English descriptions
- Cloud-hosted — no VM, no server, no Docker
- Free tier available
The trade-off:
- Requires internet connection
- Cisco devices via image upload (not pre-installed like CML)
- Newer platform — smaller community
Quick Comparison
| CML Free | CML Personal | GNS3 | NetPilot | |
|---|---|---|---|---|
| Node limit | 5 | 20 | None | None |
| Cost | Free | $199/yr | Free | Free tier |
| Multi-vendor | No | No | Yes (source yourself) | Yes (3 built-in + 6 upload) |
| AI assistance | No | No | No | Yes |
| Setup time | 2-4 hours | 2-4 hours | 4-8+ hours | None |
What I'd Recommend
If you're studying for CCNA and only need simple Cisco-only labs with 5 or fewer devices: CML Free works fine.
If you've hit the limit and need bigger labs: skip CML Personal's $199/year. Use NetPilot for AI-powered multi-vendor labs at no cost, or GNS3 if you want full manual control and have time for the setup.
If you need multi-vendor labs (Cisco + Juniper + Arista): CML can't do this at any price. Use NetPilot or ContainerLab.
Hit the 5-node wall? Try NetPilot — describe any topology and get a working multi-vendor lab with no node limits, in minutes.