I wanted to set up a small VM with NetBSD to test a couple of virt-install option. It turns out it you can get to the installer prompt quite fast.
get the NetBSD installer for serial console:
wget https://cdn.netbsd.org/pub/NetBSD/NetBSD-9.1/i386/installation/cdrom/boot-com.iso
start the install
$ virt-install \
--connect qemu:///session \
--name netbsd \
--ram 64 \
--vcpus 2 \
--disk path=$HOME/netbsd.qcow2,size=4,bus=scsi,format=qcow2 \
--controller type=scsi,model=virtio-scsi \
--cdrom=boot-com.iso \
--virt-type kvm \
--os-variant netbsd8.0 \
--graphics none \
--arch i686 \
--console pty,target_type=serial
This will start a VM in usermode networking, so no need to be root, but the VM won’t be reachable from the outside world, except if you add qemu usermode port forwarding.