The file is a virtual Cisco IOS (IOSv) image primarily used for network emulation in platforms like GNS3 and EVE-NG . It provides a full Layer 3 control-plane and data-plane environment for testing network configurations without physical hardware. Image Specifications
For detailed steps or specific issues with the process, consider checking: vios-adventerprisek9-m.vmdk.spa.157-3.m3 download