To boot an HP-UX system into single user mode, you can use the following steps:
Shut down the system if it is currently running.
Press the power button to start the system.
As soon as the HP logo appears on the screen, press the "ESC" key to enter the boot menu.
Use the arrow keys to select the "Single User" option and press Enter.
The system will boot into single user mode. You will be logged in as the "root" user and will have access to a limited set of commands and utilities.
Note: In single user mode, the system runs with a minimal set of services and does not mount any file systems except for the root file system. This is useful for performing maintenance tasks, such as repairing file system errors or resetting passwords. However, you should be careful when working in single user mode, as any mistakes you make could potentially damage your system. It is always a good idea to create a backup of your system before booting into single user mode.