Bon bah j'ai test mais ni l'un ni l'autre ne marche, (à part si le dns était important dans le programme car j'ai eu une erreur en l'écrivant)
IPAddress dns(81,253,149,10);
test:10: error: 'IPAddress dns' redeclared as different kind of symbol
IPAddress dns(81,253,149,10);
^
In file included from D:\Users\Kuro\Documents\Arduino\libraries\Ethernet2\src/Ethernet2.h:18:0,
from D:\Users\Kuro\Desktop\test\test.ino:2:
D:\Users\Kuro\Documents\Arduino\libraries\Ethernet2\src/Dhcp.h:64:2: note: previous declaration '<anonymous enum> dns'
dns = 6,
^
exit status 1
'IPAddress dns' redeclared as different kind of symbol