I recently set up an old first revision RPi in the garage with a DS18B20 sensor wired, set to monitor external ground temperature and broadcast via MQTT it was also intended to perform some other functions such garage door monitor, perhaps i'd add a PIR for alerts etc
Originally it was connected via cable through a netgear router configured as repeater and as such i could always ping it or ssh into it.
Now i've changed to an Orbi mesh system consisting of a router + two satellites and the RPi is connected via a USB wireless key at first it was ok for a few hours then seemingly lost connection so i disabled wireless power management on the RPi with sudo iwconfig wlan0 set power_save off or similar and when checking i can see it reports as off & things worked well for a while but today it fails to respond to ping or ssh as shown by;
however weirdly i was also messing around with termux on the phone and decided for no reason at all to ping the address … lo and behold we have life! and i can ssh in, update etc
Rebooting the RPi from termux i had hoped it would respond back to the PC but again it reports as dead.
Much later in the day i tried a different Windows machine and that works and so going on a updating spree which involved the laptop wifi drivers and some other Windows related updates i tried again and it now works.
I repeat very strange perhaps when the RPi has apparently become uncommunicative before it was actually the windows drivers on my laptop?? Lesson learned! before losing temper with the pi is too ping it from another device.