Libvirt is API, daemon and tool for managing of virtualization platforms and virtual interfaces and it0s used by some GUI or CLI (virsh) interfaces – but for standalone virtual machines who will don’t have any other virtualization inside (dockers, lxc…) it’s уuseless so I do a remove immediate after OS install in CentOS 7 or RedHat 7 Linux.

virsh net-destroy default
virsh net-undefine default
systemctl stop libvirtd
systemctl disable libvirtd