
Restart computers using Terminal on Mac
To restart a computer now or at a specific time using Terminal, you can use the shutdown command or the systemsetup command. The following examples show some ways to use these commands, but for complete information about them, see the shutdown command man page and the systemsetup command man page.
Tip: It’s easier to restart your Mac by choosing Apple menu 
Restart the local computer
Go to the Terminal app
on your Mac.Enter the following command:
% sudo shutdown -r now
Restart a remote computer immediately
Go to the Terminal app
on your Mac.Enter the following commands:
% ssh -l admincomputer% sudo shutdown -r nowReplace admin with the short name of a user account on the remote computer.
Replace computer with the IP address or host name of the remote computer.
Restart a remote computer at a specific time
Go to the Terminal app
on your Mac.Enter the following commands:
% ssh -l admin computer% sudo shutdown -r hhmmReplace admin with the short name of a user account on the remote computer.
Replace computer with the IP address or host name of the remote computer.
Replace hhmm with the hour and minute you want the remote computer to restart.
Restart automatically after power failure
Go to the Terminal app
on your Mac.Enter the following command:
% sudo systemsetup -setwaitforstartupafterpowerfailure secondsReplace seconds with the number of seconds before the computer starts after a power failure. This value must be 0 (zero) or a multiple of 30.
Note: You can also use Energy Saver settings to start up automatically after a power failure.