Disks won't stop at shutdown

[Tom Burton]

Thank you for all your help Ivajlo, it is appreciated. I can't help but feel that the problem is more than the power supplies not receiving the signal to switch off. When Linux completes its shutdown the drives spend a few minutes indicating online but inactive before the active lights come on. They then continuously chug away. I've had a look at the underside of the Smart-2DH array card and an LED there is flashing on and off (does anyone know what these LEDs signify). I have real concerns that it can't be good to power cycle the machine whilst the drives are active and feel that the power isn't being brought down because the array controller is indicating that it is still busy.
Yours, Tom.

[Ivajlo Yanakiev]

Yes you are right. But normaly after timeout all FS and process must kill and your server will down any way :)

Last :)

Try to start server from Knoppix live CD and and try shutdown.
If problem persist :) it is hardware based !