I try to conecting my Eternet Shild to Cayenne but the result always " Waiting for board to connect...". When i try to serial monitor with Arduino Ide show   MAC: FE-96-A0-AE-AB-AD Getting IP... DHCP Failed!
what's the solution?
have you connected the eternet shield with the routerhaving open intrnt access
DHCP failed can mean many things. The two most obvious things to check: is your ethernet cable good? are you connecting to a network that has a DHCP server? If both of those pass post back and we can check some more possibilities.
Also, if you are plugging the ethernet shield into your computer, make sure it is a crossover ethernet cable (or use an ethernet switch) and that Internet Connection Sharing is enabled.
Here's how you setup ICS: