Need help on reboot issue (hang during shutdown)

[cs]

Hi,

I have a headless colo server and sometimes (after issuing the reboot 
command) it would hang and did not reboot.

I have enabled console logging:

normal reboot:

	Sep 19 13:24:26 foo kernel: Writing entropy file:
	Sep 19 13:26:30 foo kernel: Pre-seeding PRNG:
	Sep 19 13:26:30 foo kernel: kickstart
	Sep 19 13:26:30 foo kernel: .
	Sep 19 13:26:30 foo kernel: Loading configuration files.

reboot hang:

	Sep 19 16:56:06 foo kernel: Writing entropy file:
	Sep 19 16:56:06 foo kernel: .
	<tech support reset pc>
	Sep 19 19:40:00 foo kernel: Pre-seeding PRNG:
	Sep 19 19:40:00 foo kernel: kickstart
	Sep 19 19:40:00 foo kernel: .
	Sep 19 19:40:00 foo kernel: Loading configuration files.

The console log can't tell me much...

My question is that is there other ways/settings/etc for me to diagnose 
this issue ?  Like to find out exactly what was hanging ?

Thanx.

-cs