Alternative to ESP8266 OTA on isolated network

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1

I'm using an ESP8266 in the Arduino IDE with ESP8266WiFi.h
The module is running in STA mode, connects and talks to a remote web server.
I've added ArduinoOTA.h, which works fine if the Arduino is reachable in my local network
( e.g. as 192.168.1.111 )

Unfortunately, the goal is to use an isolated Guest-Wifi-Network, where the guests are allowed to reach out to the internet, but do not see each other and are not visible to other nodes on the same router, providing this additional guest network.

When trying OTA, I get

15:45:28 [ERROR]: No Answer

Of course access to this node from the outside world isn't allowed neither.

A web server can (of course) respond back to this client.

Thus, it should be possible that this node as a client asks the server if it should update itself, get a new version from that server and perform the update.
In my understanding

  • the calls ArduinoOTA.begin(); and ArduinoOTA.handle(); start a server and perform some listening to requests?
  • the roles of server and client should be switched ?
    Am I right, and is there a similar solution available? Or is there a different solution to this problem?

Searching the web usually tells me how easily OTA works in general, any hints where to find an answer to my problem?

2

The information here might be useful to you:

https://arduino-esp8266.readthedocs.io/en/3.1.2/ota_updates/readme.html#http-server

3

I agree: seems what I'm looking for. There's more about OTA than the basic example.

Thanks so far.