KVM:defaultネットワーク

<network>
  <name>default</name>
  <uuid>...</uuid>
  <forward mode="nat">
  <bridge delay="0" name="virbr0" stp="on">
  <ip address="192.168.122.1" netmask="255.255.255.0">
    <dhcp>
      <range end="192.168.122.254" start="192.168.122.2">
    </range></dhcp>
  </ip>
</bridge></forward></network>