What shutdown command enable linux to automatically turn off power?

Author: iamlaosng searches for Linux shutdown commands on the Internet, most of which are described as follows: the shutdown command can safely shut down or restart the Linux system, it prompts a warning message to all login users on the system before the system is shut down. This command also allows you to specify a time parameter, which can be... by iamlaosng
 
Find the Linux shutdown command on the Internet, most of which are described as follows:
 
The shutdown command can safely shut down or restart the Linux system. it prompts a warning message to all logged-on users before the system is shut down. This command also allows you to specify a time parameter, which can be a precise time or a time period from now on.
 
The exact time format is hh: mm, indicating the hour and minute, and the time period is represented by + and the number of minutes. The system automatically synchronizes data after executing this command.
 
General format of the command
 
Shutdown [option] [time] [warning information]
 
The meaning of each option in the command is:
 
-K does not actually shut down, but only sends a warning message to all users.
 
-R restarts immediately after shutdown.
 
-H: do not restart after shutdown
 
-F: Skip fsck during fast shutdown and restart
 
-N: Fast Shutdown without passing through the init Program
 
-C. cancel a running shutdown.
 
Note that this command can only be used by Super users.
 
Example 1: the system shuts down in 10 minutes and restarts immediately.
 
# Shutdown-r + 10
 
Example 2: The system is shut down immediately without restarting
 
# Shutdown-h now www.2cto.com
 
In actual use, it is found that the shutdown command does not enable linux to automatically shut down the power after shutdown, no matter what parameters you use. Of course, there are also many people who have raised this question and answered a wide variety of questions, such as what requires ACPI or APM support, what needs to re-compile the kernel and add power management, etc, in fact, many people install the ready-made version. they just want to know what commands can be used to turn off the power after the system is turned off. I think the current server hardware is certainly supported. I did not do any in-depth research, but after my experiment, I found that I could use the following command to turn off the power (RHEL5 environment ):
 
1. init 0
 
2. halt or poweroff, both of which actually point to a file: consolehelper
 
3. shutdown menu on the graphic interface.
 
Of course there may be other commands, please add them.