prereq on my dev machine

sudo apt install schroot pigz debootstrap syslinux nfs-kernel-server tftpd-hpa xorriso pxelinux zfsutils-linux
cd /lab/livenet/livenet-server
rm -fR /etc/schroot/livenet
ln -s `pwd`/etc/schroot/livenet /etc/schroot/
[ -f /etc/default/livenet ] || cp -a etc/default/livenet /etc/default/livenet

zfs set sharenfs=ro rpool/livenet/backups

virsh net-edit default

<ip address='192.168.122.1' netmask='255.255.255.0'>
    <tftp root='/livenet/boot'/>
    <dhcp>
      <range start='192.168.122.2' end='192.168.122.254'/>
      <bootp file='/pxelinux.0' />
    </dhcp>
</ip>

virsh net-destroy default
virsh net-start default

ln-image --new-name bionic --create

check zfs share rpool/livenet/images/bionic

zfs get sharenfs rpool/livenet/images/bionic
NAME                         PROPERTY  VALUE     SOURCE
rpool/livenet/images/bionic  sharenfs  ro        local