For those who want a legitimate, "free" (included with study materials) experience without the hassle of hunting for IOS files, Cisco offers an official solution:
Cisco DevNet provides free sandbox environments. While this doesn’t give you a downloadable file, you can practice remotely. For GNS3, you need the actual file—so this method is more for practice than extraction.
: This is the current official method for acquiring virtual images like IOSv, IOSvL2, ASAv, and Nexus.
Select the template and point GNS3 to your local image file when prompted. : Go to Edit > Preferences > Dynamips > IOS Routers .
