Cisco IOS Release 15.9(3)M2 introduced several updates for virtual and embedded service routers, including: Cisco IOSv - GNS3
The vios-adventerprisek9 prefix indicates this is a Layer 3 router image. Vios-adventerprisek9-m.spa.159-3.m2.qcow2 Download
The vios-adventerprisek9-m.spa.159-3.m2.qcow2 file is a virtualized Cisco IOS image commonly used by network engineers and students to simulate Cisco routers in virtual environments like GNS3 and EVE-NG . This specific version, 15.9(3)M2, is part of the Cisco IOS 15.9M release train, which offers advanced routing and enterprise features for virtualized platforms. Understanding the vIOS Image Cisco IOS Release 15