qemu-system-x86_64 ... -drive file=config.txt,if=virtio
The image is a that runs in user space. It communicates with the hypervisor via virtio-net drivers. i86bi-linux-l3-adventerprisek9-15.4.2t.bin
Most "License Error" messages are due to a missing or incorrectly formatted iourc file, which contains the hostname-based key for your specific virtual machine. qemu-system-x86_64