This is just a head’s up for RaspberryPi/PiHole users - sometimes RaspberryPi PiHole needs to be rebooted. Until it is, you get some weird symptoms.
The 2.4gHz radio appeared to be completely inoperable. The first symptoms were a good WiFi signal but an inability to reach the internet. After that I could not even get a WiFi indication. (Kindle, two different models.) I even considered PiHole early and removed its DNS address and let the router pick one automatically. That didn’t work and left me considering a broken 2.4gHz radio.
What I checked and tried.
- The router’s AP/Settings have 1 6 11 channels set and I have tried Channel Widths of 20, 20/40, and 40. (20 always worked previously.)
- I downloaded a diagnostic report.
- Since this happened soon after adopting Firmware 8.1, I reverted to 8.0.2 and loaded the previous configuration.
- I have several devices that should function on the 2.4gHz band - MacBook Pro and Amazon FireStick; none worked on 2.4gHz, with either firmware.
- Oddly, my FireStick is set to 5gHz and to go through the PiHole. That worked okay in 5 but not in 2.4gHz; I presume Amazon has embedded a backup DNS address for such issues, but I can’t be sure.
What finally worked was my attempt to switch to the RPi/PiHole screen and finding it blank. I had to unplug the RaspberryPi and replug it to reboot. After that, the PiHole screen showed up everything else worked fine, too. In retrospect, I should have noticed that the RaspberryPi wasn’t in the Status/Client List. I’m back on Firmware 8.1 and everything’s working.
I hope my mistakes can help new people troubleshoot some problems.