Wakealarm for Windows

Question

On Linux, I use /sys/class/rtc/rtc0/wakealarm to schedule the computer to turn on. This uses the BIOS real time clock and allows me to fully power off the machine (not sleep). Is it possible to do something similar on Windows (server 2012 r2)?

Answer 1

It is possible to schedule the computer to 'wake' from a powered off state, especially as the OP has said he does so from linux. (For the benefit of @Emmanuel it can be done manually by entering the CMOS settings at boot and looking for RTC Alarm or similar and enabling and setting a time, then sit back and watch it happen. Just don't turn off the power supply or unplug it.) Doing so from Windows is also possible, though trickier.

AFAIK there is no CLI or native programs that do so. For starters, check the motherboard's utilities disk. I had a couple high-end boards that included CMOS access utilities with them, including RTC settings. MS does (or did) have an RTC API that some developers used to gain access to those functions as well.

There is a program UniWakeUp, which has a requirement for InpOut32, the latter being opensource, the former not. Though I suppose you're not very concerned with opensource in a Windows environment anyway.

I've found other, related, resources, but my rep won't let me give links. I found them in Google, so you can too.

Answer 2

You can start a machine from hibernate or standby or Wake-On-Lan and not from shutdown state. During normal start from shutdown, The first thing that starts is the BIOS that loaded to memory and that will be initiated and that happens when SMPS is shorted by manual power switch click operation.