in short:

Terminal

Start the terminal:

or connect from a terminal to another computer over the network using SSH:

ssh user@192.168.1.xx  

Restart command

A Linux computer or a device with Linux installed can usually be restarted with the help of the following command:

reboot

Alternatively, the reboot also works via this command

shutdown -r 0 

or

init 6

If there are not enough rights for restarting or shutting down, either a password prompt will appear:

or the following or a similar error:

shutdown: administrator rights ("root" rights) required

Here helps with Ubuntu, for example, the "sudo" command, so:

sudo shutdown -r 0

sudo reboot

or

sudo init 6

Shutdown command

Switch off or shut down goes with the command

shutdown -h 0 

oder

init 0

Ubuntu, maybe:

sudo shutdown -h 0 

or

sudo init 0

Reboot command details

reboot --help

Call: reboot [OPTION]...

Restart the system.

Options:

-n, --no-sync don't sync before reboot or halt
-f, --force force reboot or halt, don't call shutdown(8)
-p, --poweroff switch off the power when called as halt
-w, --wtmp-only don't actually reboot or halt, just write wtmp
record
-q, --quiet reduce output to errors only
-v, --verbose increase output to include informational messages
--help display this help and exit
--version output version information and exit

This command is intended to instruct the kernel to reboot or shutdown the system.
or shutdown; if it is called without the -f option, or if the system is in any
the system is in a runlevel other than 0 or 6, it will execute
execute /sbin/shutdown.

Shutdown command details

~ $ shutdown --help

Call: shutdown [OPTION]... ZEIT [NACHRICHT]
Shut down the system.

Options:

-r reboot after shutdown
-h halt or power off after shutdown
-H halt after shutdown (implies -h)
-P power off after shutdown (implies -h)
-c cancel a running shutdown
-k only send warnings, don't shutdown
-q, --quiet reduce output to errors only
-v, --verbose increase output to include informational messages
--help display this help and exit
--version output version information and exit

crontab Reboot : automatic reboot

For an automatic reboot at specific times, see: Linux crontab Reboot