What command is used to restart a Linux server?

The command used to restart a Linux server is "reboot." This command is designed specifically for that purpose, as it initiates a system restart. When executed, "reboot" safely shuts down all running services and processes before reloading the operating system. This differs from simply shutting down the system, as it is a complete cycle of shutting down and immediately starting up again.

In some contexts, one might see "shutdown" used with certain options to achieve a restart (e.g., "shutdown -r now"), but the "reboot" command is direct and widely recognized specifically for initiating a restart, making it the most straightforward option in this situation. Other commands like "poweroff" effectively turn off the system, and while "restart" conveys the intended action, it is not a standard command in Linux like "reboot" is. Thus, "reboot" is the most accurate and commonly used command to restart a Linux server.