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?

[Drew Einhorn]

Ooops, The email escaped before I was ready.

If instead of attempting to login I immediately Ctrl-Alt-F7, I see a
message that indicates the screen is locked and in a few seconds I will see
an unlock dialog. After a few second the screen blanks and I am locked up
again.

On Fri, Jul 3, 2020 at 7:13 PM Drew Einhorn <drew.einhorn at gmail.com> wrote:

> My system locks up, too.
>
> My Caps Lock key turns the light on and off.
>
> Ctrl-Alt-F2 gets me a tty2 login prompt and I can login.
>
> If I don't login but do a Ctrl-Alt-F7 before
>
>
> On Thu, Jul 2, 2020 at 7:48 PM 孙世龙 sunshilong <sunshilong369 at gmail.com>
> wrote:
>
>> Thanks to all of you.
>>
>> To Colin Law:
>> >Either it is crashed or as others suggested suspended, in which case
>> >there should be an indication of that.
>> >If crashed then look in the log as I suggested.
>> I think it's a good idea.
>> I have checked the /var/log/kern* carefully, but I have not found any
>> useful
>> information.
>>
>> To Oleg Cherkasov & Mike Marchywka:
>> >Very good suggestion indeed to unplug all USB devices if possible.  I
>> >had few times a problem with an external USB disk.  It started to fail
>> >and endless re-syncing almost hang my system so it way nearly
>> unresponsive.
>> There is no usb devices except keyboard and mouse. I'd try unplug them.
>> >BTW does "Magic SysRq" work as expected after the system hangs?
>> For details, see below. Thank you.
>>
>> To Liam Proven & Mike Marchywka:
>> >Try the magic REISUB key combination.
>> >https://en.wikipedia.org/wiki/Magic_SysRq_key
>> >Update your motherboard firmware.
>> >Is it a desktop or a laptop?
>> Sometimes the magic SysRq key works, sometimes not.
>> And only limmited functions could be provided by SysRq key,e.g.:
>> see the memory, reboot the system.I don't see any useful function,
>> though I have enabled the all possible functions.
>> >Update your motherboard firmware.
>> I can't do it indeed.
>> >Is it a desktop or a laptop?
>> IPC(Industrial Personal Computer)
>>
>> Colin Law <clanlaw at gmail.com> 于2020年7月2日周四 下午10:55写道：
>> >
>> > On Thu, 2 Jul 2020 at 14:28, 孙世龙 sunshilong <sunshilong369 at gmail.com>
>> 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.
>> >
>> > Either it is crashed or as others suggested suspended, in which case
>> > there should be an indication of that.
>> > If crashed then look in the log as I suggested
>> >
>> > Colin
>>
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>
>
> --
> Drew Einhorn
>
> On American Politics
>
> “If this were my country,” Odile said, wrinkling her nose, “I would not be
> angry.”
>
> “No?” Hollis asked.
>
> “I would drink all the time. Take pill. Anything.”
>          --- William Gibson, Spook Country, 2007.
>


-- 
Drew Einhorn

On American Politics

“If this were my country,” Odile said, wrinkling her nose, “I would not be
angry.”

“No?” Hollis asked.

“I would drink all the time. Take pill. Anything.”
         --- William Gibson, Spook Country, 2007.
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