Follow the below Steps to Start HPUX Server in Single User Mode :
1. Start / Restart the Server which you want to start in single user mode.
2.After booting the server,It will say ‘Press Any Key to interrup Autoboot’. then Press any key.
3.Then you can use ‘hpux -is‘ or ‘boot vmunix -is‘ at the ‘HPUX>’ prompt to boot into single user mode.
Thats It … 🙂