Alex had tried three images already:
: These are lightweight, high-performance L2/L3 switch binaries. While not official for public use, they are widely used in the GNS3 community for advanced switching topologies Cisco Modeling Labs (CML) : The legal way to obtain these images is through a CML subscription . Once purchased, you can export the images and import them directly into GNS3 Where to Legally Download Images Cisco IOS images for Dynamips - GNS3 Documentation cisco 4500 switch ios download for gns3
Once you have acquired a compatible image (like a vIOS-L2 or a .bin file), follow these steps to add it: Cisco IOS images for Dynamips - GNS3 Documentation Alex had tried three images already: : These
He saved the startup config. He connected the three rectangles. He assigned VLANs. He watched as the spanning-tree algorithm calculated, blocked a port, and the green dotted lines turned into actual traffic. He connected the three rectangles