Serving DHCP and DNS from a KVM guest

[Adam Reid <adam@xxxxxxxxxxx>]

Hello All,

I am trying to set up a cobbler server running as a guest on an isolated network. I'm having trouble figuring out how I can forward the DHCP and DNS traffic to this guest instead of DNSMASQ on the host.  So far I have only tried to get dhcp working by enabling the 
'allow-dhcp-server' on a guest named test and setting the $DHCPSERVER variable through a filterref parameter element. I figure If I can get this 
working I can use this filter as a basis for DNS. 

In my guest the filter is applied to the only network interface setting DHCPSERVER to the IP of my cobbler VM.

    <interface type='network'>
      <mac address='52:54:00:6b:56:ab'/>
      <source network='internal'/>
      <target dev='vnet2'/>
      <model type='virtio'/>
      <filterref filter='allow-dhcp-server'>
        <parameter name='DHCPSERVER' value='192.168.100.2'/>
      </filterref>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x03' function='0x0'/>
    </interface>

And the internal network is defined as:

<network>
  <name>internal</name>
  <uuid>c1aef8ea-9d30-7514-5eb4-5ffbc235cffb</uuid>
  <bridge name='virbr1' stp='on' delay='0' />
  <ip address='192.168.100.1' netmask='255.255.255.0'>
  </ip>
</network>

My understanding of the filter is that when it is applied to a hosts interface it should allow DHCP requests to go to a server other than the host system. Is this correct? Are guests allowed to serve DHCP to other guests?

Does anyone have any suggestions or experience with this?

Thanks in advance,

Adam Reid