This ability would be useful for many users.  Settings/Schedules already has a Parity Check section, we just need the ability to wake the system if needed, preform a parity check and when finished go into S3 sleep if no activity.

Seems a little unclear. You want a system that only wakes up to do a parity check?

 

From the title of this topic I thought perhaps you had in mind waking up to sync data from some other system, but I don't see the point of just waking up to do a parity check.

 

And what would do the waking? Usually this is done by another system on the LAN sending some special data to the MAC address of the system to be awakened. So the schedule wouldn't be under the control of unRAID anyway.

 

Maybe you could elaborate.

The request seems to imply that you think unRAID can trigger a ‘wake’?    This is not the case as the ‘wake’ always needs to come from an external hardware source.   This can either be a feature built into the B’iOS of the server, or a special ‘Wake on LAN’ packet from another machine.  Not all servers have hardware that supports one of these options which is one of the reasons there is no built-in ‘sleep’ capability in unRAID. 

Unraid does include the rtcwake command, which will work with some boards to inject a wake up time into the BIOS.

 

At no point was this set up automatically, and it's not guaranteed to work with all hardware or combinations thereof.

 

I could be wrong, but I don't remember any plugins that tried to automate the usage of the command, so if your system was set up to use rtcwake, it was something done manually, possibly with a command in the go file.