The software image file can be an .xos file, which contains an ExtremeXOS core image, or an .xmod file, which contains an ExtremeXOS modular software package.
You can identify the appropriate image or module for your platform based on the file name of the image. The Summit and ExtremeSwitching switches use the summitX- filename prefix. The exceptions are the ExtremeSwitching X870 and X690 series switches, which use the onie- prefix (for example: onie-22.2.1.2.xos).
For additional installation requirements see the sections, Installing a Core Image and Installing a Modular Software Package.