QCOW2 is the native disk format for QEMU/KVM:
Place the firmware file in the root directory of your TFTP server. fgtvm64kvmv723fbuild1262fortinetoutkvmqcow2 upd
Version 7.2.3 (build 1262) specifically introduced improvements in SD-WAN stability, ZTNA tag propagation, and security fabric integration. QCOW2 is the native disk format for QEMU/KVM:
indicates it is built for 64-bit virtual environments using the KVM architecture. ZTNA tag propagation