How can you temporarily change the hostname of a Linux system?

To temporarily change the hostname of a Linux system, the correct command is hostname new-hostname. This command modifies the system's hostname until the system is rebooted; at that point, the hostname will revert to whatever is set in the configuration files, typically defined in /etc/hostname or /etc/sysconfig/network.

Using the hostname command allows users to change the current hostname of the machine without requiring superuser privileges, though the change will not persist after a reboot. This method is quick and effective for testing or temporary changes, such as in a development environment.

The other options do not function as intended for temporarily changing the hostname. For example, set hostname new-hostname is not a valid command in Linux, as the set command is not used for hostname changes. Meanwhile, hostnamectl new-hostname is incorrect because the correct usage of hostnamectl would involve the set-hostname argument for making changes effectively. Finally, change-hostname is not a recognized command in Linux systems.

Therefore, using hostname new-hostname is the appropriate method for effecting a temporary change to the hostname.