Assigning IPs

IPs are generally assigned to guest VMs via a DHCP daemon on the host.

virsh net-update default add ip-dhcp-host \
      '<host id="MACADDRESS" ip="IPADDRESS"/>' \
      --live --config

Default Network Limitations

https://libvirt.org/firewall.html

The default network has some limitations. It's possible to re-create it (https://jamielinux.com/docs/libvirt-networking-handbook/custom-nat-based-network.html).

One alternative is to use libvirt hooks to rewrite the iptables rules when updated: https://www.libvirt.org/hooks.html.