Fgt-vm64-kvm-v7.2.3.f-build1262-fortinet.out.kvm.qcow2

is the exact version of the operating system (FortiOS). The ".f" is the most fascinating three letters in the whole string.

The filename Fgt-vm64-kvm-v7.2.3.f-build1262-fortinet.out.kvm.qcow2 represents a specific virtual appliance image for FortiGate Next-Generation Firewalls (NGFW) Fgt-vm64-kvm-v7.2.3.f-build1262-fortinet.out.kvm.qcow2

Add at least two Virtual Network Interfaces (vNICs)—one for WAN (Port 1) and one for LAN (Port 2). Disk: Import the .qcow2 file as the primary boot disk. Initial Configuration: Once booted, the default login is admin with no password . Immediately configure the management IP: is the exact version of the operating system (FortiOS)