The official doc seems too complicated OpenWrt on VirtualBox HowTo
- Download and install VirtualBox. On Windows add to PATH envs
C:\Program Files\Oracle\VirtualBox - Get an OpenWrt image
openwrt-x86-64-combined-ext4.img.gzfrom targets/x86/64/ folder. Direct snapshot download - Uncompress the image:
gunzip openwrt.img.gz - Convert it to native VirtualBox format:
VBoxManage convertfromraw --format VDI openwrt.img openwrt.vdi