will alarm a red alert when deploying Haojing.
###set the ethernet first.
byte mac[] = { 0xDE, 0xAD, 0xBE, 0xEF, 0xFE, 0xED};
IPAddress ip(192, 168, 8, 222); // set the fixed IP of ethernet
IPAddress dns_server(172, 16, 0, 1); // dns in office
IPAddress gateway(192, 168, 8, 1);
IPAddress subnet(255, 255, 255, 0);
###and deploy server
char server[] = "xxx.baixing.com";
###other settings
postingInterval the frequency of checking (by ms)