The dnsmasq guys have confirmed that the code exposing the environment variable DNSMASQ_MAC in case ipv6 will be out in the coming week as an official release. Meanwhile, I had a chat with mrjester on #ipv6 regarding fields which are supposed to be useful to users in case DHCPv6 is used. I've attached the chat history. Now, coming to the API, I do think that supporting --dhcp-script will be a good option. So that we don't land up with half-implementations. So I am hoping that we are in a position to finalize the virNetworkDHCPLeases struct now. In case of DHCPv6, we should be exposing expirytime, MAC Address, IP Address, hostname, client DUID, IAID and the interface name to which the lease is provided (which can be obtained from the env variable DNSMASQ_INTERFACE) I personally think the easiest way would be to have all possible values in the virNetworkDHCPLeases struct and let the user decide which one he wants. The ones which are not available, will be set to NULL. -- Nehal J Wani