On several occasions now I have needed to power cycle our DL4100 in order to be able to access it. It is like it has totally locked-up or crashed.
All the lights are on as they should be but you cannot cycle through the front display panel using the buttons. Usually the front power button still works to power the system down, however this morning it required pulling the power supply.
I just had a quick look through the logs and there are several “HWlib unable to read HDx temperature” which I think coincide with the lock-ups.