[CentOS] SOLVED - Shutdown/poweroff does not power off machine

Mon Mar 1 23:27:51 UTC 2010
Michael Klinosky <mpk2 at enter.net>

ken wrote:
>> No, I'm not the OP. But, I found a solution for my system.
>>
>> During boot, I noticed an error line --
>> "BIOS fails cutoff age - ACPI might not work. Use acpi=force to fix."
>>
>> So I did; the machine now actually turns off after shutdown.
> 
> Great work, Michael!  Where did you insert/type in "acpi=force"?

In /boot/grub/grub.conf, there is a line (there may be more) that begins 
with 'kernel' - put it at the end of that line.