GIAC Foundational Cybersecurity Technologies Practice Test

The command that reveals the mode in which the Linux operating system is currently running is the runlevel command. This command displays the current runlevel, which indicates the state of the operating system, such as whether it is in a multi-user mode, graphical mode, or single-user mode. Each runlevel has a specific function: for instance, runlevel 3 is typically used for multi-user mode without a graphical interface, while runlevel 5 is used for multi-user mode with a graphical interface.

While other commands like chkconfig, uname, and systemctl serve important functions within the Linux environment, they do not specifically indicate the current runlevel. Chkconfig is primarily used for managing system services and their runlevels. The uname command is used to display system information, such as the kernel version and architecture. Systemctl is part of Systemd, which manages system services and does not provide information on the traditional runlevel directly, as it uses target units instead.