Question

Hello,

I'm facing sporadic problems with some ESP32 devices which should connect to a RUT240 router.

The router is connected via WAN Port, the ESP32 via wifi.

I was able to observe that the devices try to connect but after a "daemon.info unhandler[2363]: modem_init[3]" the connection drops immediatly. This is a relatively rare event but quite annoying. The fix is to remote reboot the router.

What does this error mean and how can I fix it?

Best regards

Dennis

Comments

I attached a troubleshoot log where I tried to fix my problem.

My normal procedure is:
1) Turning wifi off and on, so that my devices can reconnect
2) Power cycle my devices by toggling the Output pin

And after that
3)restarting the router.

In this case the first both didnt help. But after restarting the router everything was working again.

Best regards

Dennis

Answer 1

Hello,

modem_init is not related to WiFI and it is not an error.

Do all of the devices get disconnected at the same time or they fail to connect via WiFi?

The next time a similar event occurs, I would like you to attach a troubleshoot file to your question. Please, replicate the issue, then access router's WebUI, go to System -> Administration -> Troubleshoot section and download troubleshoot file from there.

Does your ESP32 provide some logs after such events occur, could you share them too?

Attach files by editing your question.

Best regards,

Comments

Hello,

thanks for that quick answer.

Unfortunately its quite hard to reproduce those events. In my lab enviroment I cannot replicate those events. Those occur only in the field and from there the logging for the ESP is turned off / not reachable.

I tried to download a troubleshoot log last time but for some reason it didnt work, I will try that next time.

As said: These errors occur very rarely and on different systems.

The error modes are also quite different, sometimes all ESP32s cannot connect, sometimes just one. I suspect different reasons for these 2 behaviours.

For more background info:

The ESP32s power supplies are switched via the output port of the RUT240. Toggling the output pin via webUI(so power cycling the ESPs) doesnt solve the issue. There are up to 8 ESPs connected to one router. So I think the problem lies somewhere in the router.

I'm very curious about the "daemon.info unhandler[2363]: modem_init[3]" message, since it was interleaved with the connection attempts of one ESP32 - can you give me a pointer what this error means?

Sorry, that I cannot provide further information from the router logs, I will try that next time.

Best regards

Dennis

---

modem_init simply denotes messages or rather instructions related to router's modem initialization sequence. These messages provide details about modem operation state and capabilities, which might be helpful troubleshooting mobile connectivity issues.

Therefore, as previously mentioned, they should not be related to WiFi

---

Hi,

I have some troubleshoot logs, with error state, recovery attempt and fix.

How can I provide them to you? I cannot find an attachment function here?

Best regards

Dennis

---

You can send it in a private message or attach by editing your question.

---

The ESPs do tend to disconnect and these events are rather inconsistent. However, the logs do not indicate anything else, regarding possible reasons, such as low acknowledgements, inactivity, authentication issues, etc, thus, it is difficult to estimate what could be the causes.

A RUT240 firmware update can be attempted to the latest version, to see if that provides any improvement. 

Other than that, for additional details, another option could be to install TCPdump from Services -> Package manager and enable packet capture on wireless LAN (wlan0) interface for some time. Maybe the capture would reveal more into what could be happening.

Best regards,