How can I investigate the cause of total hang? Is there some information that I should pay attention to in order to get some hint?

[Mike Marchywka]

On Thu, Jul 02, 2020 at 09:28:04PM +0800, 孙世龙 sunshilong wrote:
> Hi，
> Thanks to both of you.
> 
> >Does the Caps Lock light still go on and off when you hit the key?  If
> >not then the machine has probably crashed completely.
> >On reboot look in /var/log/syslog to see what it says.
> 
> 
> >Try to switch into console mode with Alt+F3 or Alt+F4, login and check
> >dmesg messages if there are any.
> 
> No response to any key(e.g. Caps Lock, Alt+F3, etc).
> Any more methods that I should try.

Did not see the prior suggestion :) After installing gdm, I discovered
a new hang mode involving the screen saver although the console
was still available initially but then everything hung. 
Eventually I hit the power button briefly,
expecting to restart, and everything came right back. 
I guess in that case it went into a suspend mode.       

You could try unplugging anything plugged in and plugging it back in.
Maybe even plugging in a second keyboard. Although probably deadlock
or just a simple crash. 


> 
> Thank you for your attention to this matter.
> Best Regards.
> 
> 孙世龙 sunshilong <sunshilong369 at gmail.com> 于2020年7月2日周四 下午2:09写道：
> >
> > Hi,
> >
> > My x86 machine sometimes hangs, suddenly not responding in
> > any way to the mouse or the keyboard.
> >
> > How can I investigate the cause of total hang? Is there some
> > information that I should pay attention to in order to get some hint?
> 
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mike marchywka
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marchywka at hotmail.com
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