Ben,
thank you for your reply.
I forgot to mention in my email that I ran the DHCP server on the same linux host (just for testing at the moment). It is ISC DHCP3.0pl2, and is configured to listen on eth1 (ie. the private network interface) only.
The plugin cannot see locally generated ethernet frames.
You should be able to use DHCP locally provided you configure the plugin to talk unicast to a specific local address. This causes the plugin to talk pure IP to the DHCP server, usually via the loopback device. You need to use a different local address as the relay address (you can't use 127.0.0.1 as ISC DHCP treats this as a special non-compliant debug mode and hence doesn't respond correctly). The documentation with the plugin explains this. Having said that, although I tested this mode of operation when I originally wrote the plugin, others have reported they were unable to reproduce my results and I'm still at a loss to why that is.
Regards, Ben.
-- Ben McKeegan Firewall Developer Netservers.co.uk
