Question Problems with IP addresses; router configuration, http

Oct 13, 2019
Hi folks!

I am currently playing with homebridge (software that allows DIY sensors to be integrated into Apple Homekit via a Raspberry Pi), doesn't matter if you don't know it.
The setup is as follows:
A Wifi-device with temperature/humidity sensors (ESP8266) sends a json-file to a raspberry via ethernet.
I got two identical setups, one is working, one isn't, and I can't the heck figure out what the problem is.
The working one has the IP and the non-working one has Problem is, I can't reconfigure the .210 one because it's embedded in epoxy... (not my smartest move, but it was working prior to that, and the epoxy can't be the problem, because the SOAB is online and connected to the router, therefore also sending data.)

What I need to know is, what could be a possible configuration-problem with my router, that doesn't allow the .210 one to communicate but the .20 is fine.

Sorry if this is complicated, but the homebridge/esp8266-stuff really doesn't matter, I know for sure that the ESP is doing its things and the homebridge is fine too. The problem has to lay in the routers config...

Thanks for any tips or leads!
I assume you have another ip in the same subnet that you are attempting to talk to both these machines from.

The traffic is not even going through the main router chip so there is no configuration than can really affect this. There are wireless setting but if both are wireless and one work but not the other then it is not a wifi issue.

It almost has to be some issue with a subnet mask. I suppose you could have a duplicate IP address but that is not likely.

I do not know how much you can do with these devices. What you want to do is attempt to ping the IP addresses from some device. You also want to look in the ARP table to see if even though it does not respond to ping it might respond to a ARP. You should see the mac address mapped to the ip address.

If ARP or ping works you have basic communication and the problem must be more complex in nature.