On a Rasperry PI there is an option to attach a pushbotton on the GPIO3 pins and this gives a start/stop switch to the Pi. Before the installation of omv this feature did work fine - it´s activated in the /boot/config.txt (dtoverlay=gpio-shutdown)
AFTER the plain installation of omv (wget -O - https://github.com/OpenMediaVault....) this feature does not work any more for shutdown. To me it seems that omv disables all GPIO...
A start of a PI by closing the GPIO does work, so the general configuration/functionality seems to be OK....
I did test it with a plain Rasberian (buster) + current updates on a Raspberry PI 3 B+ v1,2 . omv 5.6.2.-1
Needless to say omv itself works without any problems.
Any hints would be fine
Greetings from Graz