A single CCIE lab attempt costs $1,600. A full hardware lab costs $10,000+. EVE-NG (Community Edition) is free. IOU is free—if you use the keygen.
Here is the reality of the most controversial file in the networking lab community. Before understanding the keygen, you must understand IOU. Cisco’s IOS on Unix (later called IOL – IOS on Linux) was never meant for public release. It is an internal Cisco binary that runs Cisco IOS as a native Linux process—without hardware emulation. cisco iou keygen.py download eve-ng
Dynamips is accurate but slow. IOU can boot 50+ routers on a laptop with 16GB RAM. For large BGP or MPLS topologies, IOU is the only practical option. A single CCIE lab attempt costs $1,600