. For version 7.2.2, look for filenames specifically containing Virtual Environment Support : It is commonly used in network simulation tools like Official Download & Access
"Direct download for the Cisco IOS-XRv 9000 Virtual Router (Release 7.2.2). This package, identified by the filename xrv9k-fullk9-7.2.2 , provides a full virtualized instance of the IOS-XR operating system for lab testing and network simulation." Xrv9k-fullk9-7.2.2 Download
Running xrv9k-fullk9-7.2.2 without a license severely limits throughput and feature access. Version 7.2.2 uses Smart Licensing (call-home) by default. . For version 7.2.2
: After booting, run: