The reboot Command¶

The reboot command is used to restart a linux system. However, it requires elevated permission using the sudo command. Necessity to use this command usually arises after significant system or network updates have been made to the system.

Syntax¶

reboot [OPTIONS...]

Options¶

• –help : This option prints a short help text and exit.
• -halt : This command will stop the machine.
• -w, –wtmp-only : This option only writes wtmp shutdown entry, it do not actually halt, power-off, reboot.

Examples¶

1. Basic Usage. Mainly used to restart without any further details $ sudo reboot However, alternatively the shutdown command with the -r option $ sudo shutdown -r now

Note that the usage of the reboot, halt and power off is almost similar in syntax and effect. Run each of these commands with –help to see the details.

1. The reboot command has limited usage, and the shutdown command is being used instead of reboot command to fulfill much more advance reboot and shutdown requirements. One of those situations is a scheduled restart. Syntax is as follows $ sudo shutdown –r [TIME] [MESSAGE] Here the TIME has various formats. The simplest one is now, already been listed in the previous section, and tells the system to restart immediately. Other valid formats we have are +m, where m is the number of minutes we need to wait until restart and HH:MM which specifies the TIME in a 24hr clock.

Example to reboot the system in 2 minutes $ sudo shutdown –r +2

Example of a scheduled restart at 03:00 A.M $ sudo shutdown –r 03:00 3. Cancelling a Reboot. Usually happens in case one wants to cancel a scheduled restart

Syntax $ sudo shutdown –c [MESSAGE] Usage $sudo shutdown -c "Scheduled reboot cancelled because the chicken crossed the road"

1. Checking your reboot logs $ last reboot