On a production Linux/Unix server, which user must you generally be to shut down the system?

In a Linux/Unix environment, the user that generally has the permission to shut down the system is the root user. This is because the root user holds the highest level of privilege in the system, allowing for the execution of administrative tasks that affect the entire operating environment, including shutting down or rebooting the system.

Other users, including system administrators, may have elevated privileges through the use of sudo or specific configurations, but they may not inherently possess the ability to shut down the system without invoking superuser access. The root user does not require any additional permissions or authorization to perform this action. Therefore, while other roles such as sysadmin or administrator may have associated privileges, they typically depend on the rights granted to them, which can differ between environments. The root user, however, is universally recognized as the one who can execute shutdown commands without restrictions.