To avoid having to run cables I have used a Netgear WGPS606 to wirelessly connect computers on my desktop with my broadband connection. When checking the log files on my Linux box I noticed that the Netgear unit was causing my log to fill up with DHCPDISCOVER/DHCPOFFER:
Jun 20 23:21:21 xxx dhcpd: DHCPDISCOVER from <mac>(WGPS606) via eth0 Jun 20 23:21:21 xxx dhcpd: DHCPOFFER on 10.1.1.191 to <mac>(WGPS606) via eth0 Jun 20 23:21:41 xxx dhcpd: DHCPDISCOVER from <mac> (WGPS606) via eth0 Jun 20 23:21:41 xxx dhcpd: DHCPOFFER on 10.1.1.191 to <mac> (WGPS606) via eth0 Jun 20 23:22:01 xxx dhcpd: DHCPDISCOVER from <mac> (WGPS606) via eth0 Jun 20 23:22:01 xxx dhcpd: DHCPOFFER on 10.1.1.191 to <mac> (WGPS606) via eth0
It is all very strange since the MAC address for which the DHCP discover is sent is the wireless NIC. But the wireless NIC has a static IP address and should not need to request a DHCP address in the first place. Furthemore, the DHCP server is on the LAN side of the Netgear box.
Netgear support has been unable to assist so in the end I had to blacklist the WGSP606 using the following few lines in dhcpd.conf:
host wgps606 { hardware ethernet <mac>; ignore booting; ignore bootp; }
Apart from this the WGPS606 has been doing a great job for now almost a year.