The string fgtvm64kvmv721fbuild1254fortinetoutkvmqcow2 is not spam or random characters. It is a from Fortinet’s virtualization pipeline. For a network engineer, it represents a deployable FortiGate firewall on KVM with a specific build of FortiOS 7.2.1.
If that assumption is correct, I'll proceed with the following deliverables:
Indicates a "Feature" release (as opposed to a "M" Mature release).
The string fgtvm64kvmv721fbuild1254fortinetoutkvmqcow2 appears to represent a image file, specifically packaged for KVM (Kernel-based Virtual Machine) in QCOW2 format (QEMU Copy-On-Write version 2).