Photons on occasion take 7 minutes trying to connect, then reboot before successful

We have Photon based products, and are noticing a strange quirk on rare occasions when they try to connect to the Wi-Fi network. They are using Device OS version 1.1.1.

When the issue is seen (we’ve seen it at least five times now) it will be on a device and network that normally connects fine when powered up. It will just be once in a while, when the device is first powered up, this is what we see:

  • LED does the slow flashing green, like it is beginning the Wi-Fi connection attempt
  • It then goes to the fast flashing green, like it is about to connect
  • But then, instead of connecting like usual, it stays fast flashing green for ~15s
  • It then blinks white, and begins alternating white for 1s then blinking green for 4s
  • It repeats alternating white and green like this for ~7 minutes!
  • It finally appears to reboot itself, and then connects normally/successfully this time

Any ideas what would be causing this? As I mentioned, with the same Photon on the same product in the same physical location connecting to the same router, it normally connects fine. Just once in a while this weird issue is seen.

Thanks!

Hi @sddw - there have been innumerable improvements to Device OS with respect to connectivity since 1.1.1. Are you willing to test against 2.1.0? If you can reproduce the issue, can you gather logs and present them here via a neutral firmware logger like Cloud Debug (Releases · particle-iot/cloud-debug · GitHub)?

Hi @marekparticle, thank you for responding. Looking at the logger link you provided, it says “Device OS 1.5.2 or later is required”. Do I understand correctly, that I cannot use this method to log what is happening on our product running OS 1.1.1? Is there some other firmware logging method available for this OS, lower level than our application’s serial debug logs?

I will be curious to try OS 2.1.0 and compare, though it may not be trivial to update all units in the field. In the meantime, is there any info you can share regarding what the described LED sequence may mean? What does the cycling white (1s) and blinking green (4s) LED indicate?

Thanks!

Hi @sddw - you could use the deprecated GitHub - rickkas7/photon-clouddebug: Special code for debugging cloud connection issues with the Particle Photon.

Typically it points to an issue with the local connection (white - wifi off - means the device is resetting the wifi connection, green means its struggling to resolve the wifi network). Logs will help, but logs on 2.1.0 in parallel are ideal.