I have two pi's (a Pi3 and a Pi ZeroW) running very similar software to measure temperatures. Both connected via the same WIFI
They have both been running satisfactorily for months (with only the occasional hiccup which has been resolved with a remote reboot with VNC) but the Pi3 dropped offline at 18:19 GMT on 18th April and I have not been able to restore connectivity to the dashboard via a software reboot via VNC of a hardware reboot via the power switch. I have full connectivity via VNC to the PI so it is basically working.
I have made no deliberate changes to any software on either machine for weeks, so am just trying to eliminate other possibilities before I consider more serious issues like SD card corruption. (any others suggestions would be welcomed)
Thanks.