Jan 8, 2013 at 1:47 PM

I have a flat network. Networking doesn’t work however including Arduino web server unless I add a default gateway ! Seemed to hang getting time update.

Added static byte gateway[] = {192,168,1,254};   in user defs
And used every time there is an
Ethernet.begin with :-
Ethernet.begin (mac, ip, dnsserver, gateway);

Jan 10, 2013 at 11:17 AM

The arduino ethernet library will generate the gateway address automatically by changing the last digit of the Arduino IP address to 1.

If your gateway is not at then you will have to add it manually, like you did.