[SOLVED] HTTP.Request internal error ?

function SendData(data) {

  data.DeviceName = Name;
  data.DeviceType = Device;
  data.DeviceModel = Info.model;
    
  let params = { 
                 method: "POST", 
                 url: CONFIG.DataURL, 
                 headers: CONFIG.Auth,
                 content_type: 'application/json',
                 body: JSON.stringify(data)
                };
                
  Shelly.call("HTTP.Request", params, function (res, error_code, error_msg, ud) {
     if (!error_code) {
        if (res.code === 200) {
           DeleteKVSandQueue(ud.key);
           print("SendData: Data Sent", JSON.stringify(ud));
         } else { print("SendData: HTTP Status code", res.code); }
      } else { print("SendData: Error", JSON.stringify(error_code), JSON.stringify(error_msg)); }
  },
  data)
}   

I have two Shelly 4 Pro PM (fw 0.11.3) in the same local network, both connected with ethernet and set up identically. I can access the WebUI on both of them.

One of them has started to produce the error message: SendData: Error -114 "Resource unavailable: HTTP connect error -1!". It even does this on the first HTTP Request after a reboot.

Have I broken something in the device ?

Yes. That's easy to guess, but the KVS value and the Queue persists. It's the HTTP Request itself that fails.

Alright. The Full Debug log (that I hadn't noticed until now) shows that DNS query for the target domain fails. It seems the ISP DNS is no longer responding to queries from one of my Shellys. That is very strange, but it is something I can workaround.

I have reconfigured the local DHCP to issue google DNS servers to the Shelly devices and that fixed the problem.

Sorry for taking every ones time.