If you install all the packages required to run a KVM/QEMU host on CentOS, the qemu-system-x86_64 binary will not be installed. I don't know why this is true.

On Red Hat based distros you can run KVM/QEMU without ever knowing qemu-system-x86_64 exists. I've been using virt-install for years and thought it was the only way to build a VM.

I stumbled over this weirdness while learning Cumulus. The official doc is written for Debian based OSes, so when you try following these docs and try typing kvm you will see bash: kvm: command not found... nor can you install it from yum. It does not exist for CentOS.

So you must install qemu-system-x86_64 and s/kvm/qemu-system-x86_64 when you define (create) the Cumulus VMs per the Getting Started doc below.

https://docs.cumulusnetworks.com/cumulus-vx/Getting-Started/Libvirt-and-KVM-QEMU/