If we want to "wake up" the computer at a certain moment, we can use the rtcwake command. rtcwake hibernates or suspends the system and to automatically wake from it at a specified time, for example:
To hibernate your system for for 2 hours and then wake up automatically, run
# rtcwake -s 7200 -m disk
- -s 7200: It is the time in seconds that the system will be hibernating, then it "wakes up"
- -m disk: In this mode memory content is written to the disk
- - man rtcwake