Cisco have confused me a little in the way they have brought their simulator to market. First it was VIRL and free, then CML was announced and the name change blamed on marketing. Now we have both. Here is a birds eye view of each for reference. I’ve also included GNS3 as it is worth considering if you’re in the market for an emulation tool.


  • Part of the /dev/innovate program at Cisco
  • In Beta at the time of writing
  • Community supported
  • Runs on Linux KVM Hypervisor / OpenStack frontend
    • This can be installed bare metal or run via VMWare Fusion / Workstation / Player etc
  • Local hardware model (laptop / desktop)
  • Supports IOS, IOS-XE, IOS-XR and NX-OS
  • No Layer 2
  • Annual Licence either Academic or Personal ($80 or $200)
  • Capped at 15 nodes


  • Corporate Edition
  • TAC Supported
  • Client / Server Model
  • IOSv only today
  • NXOS support roadmapped
  • Heavy server requirements
    • Min: 4 Core CPU / 16 GB RAM for basic 15 node limit
    • 16 Core CPU / 128 GB RAM for full 50 nodes
  • Server runs Ubuntu image
  • Java Client (oh Cisco, why do you try my patience so?)
  • $13,000 Base Install (15 node limit)
  • 5% discount for 50 nodes, 10% for 100
  • More pricing detail and other useful information here

All-in-One Virtual Machine

  • Free
  • Limited version of VIRL
  • 3 Node Development Environment for the Open Network Environment Platform Kit (onePK)
  • Designed to allow would-be app writers to develop and test their Apps


  • Free
  • Community Supported via the GNS3 Jungle
  • Multi-Vendor – Cisco, Juniper, HP, Arista, Citrix and Brocade
  • L2 Supported using Cisco L2IOU Images (native on Linux / Solaris only, VMs on Windows / Mac)
    • Although features relying on L3 Hardware such as  L3 Etherchannel, ISL trunks, DHCP snooping, Private VLAN, SPAN/RSPAN/ERSPAN, Port-security, Voice VLANs, MLS QoS and QinQ won’t work
  • Supports any Cisco platforms available as a virtual machine using VitualBox or Qemu



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