Hi, we use small embedded X86 linux servers equipped with a single physical ethernet port as a gateway for an IP video surveillance application. Each downstream IP cam is mapped to a separate virtual IP address like this: real eth0 IP address= 192.168.1.1, camera 1 (eth0:1) =192.168.1.61, camera 2 (eth0:2) =192.168.1.62, etc. etc. all on the same eth0 physical port. This approach works well, except that a specific third-party windows video recording application running on a separate PC on the same LAN, automatically pings the virtual IPs looking for unique who-has responses on system startup and, when it gets back the same eth0 MAC address for each virtual interface, freaks out and won't allow us to subsequently manually enter those addresses. The windows app doesn't mind, tho, if it receives no answer to the who-has ping. My question - how can we either (a) shut off the who-has responses just for the virtual eth0:x interfaces while keeping them for the primary physical eth0 port, or, in the alternative, spoof a valid but different MAC address for each virtual interface? Thanks!