Special thanks to Cisco Systems and the GNS3 community for their resources and support in creating this guide.
Once you have installed the IOS image, verify that it is working correctly by:
For the keyword (meaning stable on 2.1.9), the 15.1(4)M6 image is best for advanced features, while 12.4(25d) is rock-solid for CCNA labs.
A virtualized router that supports modern IOS 15 features without hardware emulation bugs.