hi, one of the process of hpux startup is this ISL where it consults the AUTO file. is this AUTO file resident in disk?
thanks
If you are running LVM, it's in the BDRA (boot data reserved area) of the boot disk. The boot disk will almost certainly be one of the physical volumes in vg00. When I do a "vgdisplay -v vg00", the last thing I see in that my only physical volume is /dev/dsk/c0t1d0. I can verify that this contain my AUTO file by using the command "lifls -l /dev/dsk/c0t1d0". Then I can display the contents of it by typing "lifcp /dev/dsk/c0t1d0:AUTO -". And in my case it simply displays "hpux".
Be careful with lifcp, it can render a disk unbootable very easily.
whew.. really, i wont dare to try anything that cause any downtime of the system. but on the other hand, isnt it vital for any diligent system admins to know the startup process of the unix under his care?
SO, does running linux back home helps in this area?
Yes, absolutely. It is vital for a sys admin to understand the boot process.
Any command run by root has some potental for danger. Something like: "df -k > /etc/passwd" could be a real disaster. But vgdisplay and lifls should be as safe as, say, df. Both just try to dispaly some information. Neither wants to change anything. It's lifcp that is more dangerous. It is a file copy program.
I don't know about linux, so I can't compare it to HP-UX.
All experience helps, but running linux at home does not substitute for understanding your high availability production platform (in your case, HPUX).
Perhaps this analogy helps:
Can you play the guitar? Can you play the violin? They are both stringed instruments and playing one provides experience for the other... HOWEVER, only highly accomplished and experienced violin players are great violin players and only highly accomplished and experienced guitar players can be great guitar players...
... the same is true for computer operating systems.... 
hey, i like the analogy.... and yes, i played guitar.. had been playing for 5 years now.. not as what u described " highly accomplished and experienced " guitar players.. but working towards it...
okay, the boot process say for hpux, aix and solaris are going to be different, right?
seems like not that helpful to install linux after all....... will think about it.. thanks pals!!