Very Computer

by Ia » Sun, 21 Jun 1998 04:00:00

A strange request perhaps, but I want to test the softdog watchdog
facility, so I need to crash my 2.0.34 box, but can't think of a way
to do this. Does anyone know of a way? I know that a software watchdog
can fail to reboot a locked machine, but I want to see if I can
provoke it into action.

--
Ian - Edit address before mailing. | Have you got a question you want to ask
Running Linux in the UK. | Usenet? Search www.dejanews.com first!
-- There are no facts, only opinions --

by **Atarax** » Mon, 22 Jun 1998 04:00:00

Ian cracked the ice around my prison with these words:
|A strange request perhaps, but I want to test the softdog watchdog
|facility, so I need to crash my 2.0.34 box, but can't think of a way
|to do this. Does anyone know of a way? I know that a software watchdog
|can fail to reboot a locked machine, but I want to see if I can
|provoke it into action.

As root: kill -9 1

--

Official Defunct Poet of alt.books.m-lackey
Proud Red Hat Linux user
Fan of Sci-Fi, Fantasy, fine music, and M:TG
Very Strange Individual

by Ia » Mon, 22 Jun 1998 04:00:00

Quote:> Ian cracked the ice around my prison with these words:

>> A strange request perhaps, but I want to test the softdog watchdog
>> facility, so I need to crash my 2.0.34 box, but can't think of a
>> way to do this. Does anyone know of a way? I know that a software
>> watchdog can fail to reboot a locked machine, but I want to see if
>> I can provoke it into action.

> As root: kill -9 1

That's more a case of nothing running rather than a crash, but it's a
definite start, I'll have a go. Annoyed I didn't think of it myself in
fact..

--
Ian - Edit address before mailing. | Have you got a question you want to ask
Running Linux in the UK. | Usenet? Search www.dejanews.com first!
-- There are no facts, only opinions --

by Ia » Mon, 22 Jun 1998 04:00:00

>> Ian cracked the ice around my prison with these words:

>>> A strange request perhaps, but I want to test the softdog watchdog
>>> facility, so I need to crash my 2.0.34 box, but can't think of a
>>> way to do this. Does anyone know of a way? I know that a software
>>> watchdog can fail to reboot a locked machine, but I want to see if
>>> I can provoke it into action.

>> As root: kill -9 1

> That's more a case of nothing running rather than a crash, but it's a
> definite start, I'll have a go. Annoyed I didn't think of it myself in
> fact..

Hmm, as it happens, this doesn't work. Anything but -INT has no effect
on init, using -INT causes a clean reboot, exactly as if I'd typed
"reboot".

Does anyone else have any ideas??

--
Ian - Edit address before mailing. | Have you got a question you want to ask
Running Linux in the UK. | Usenet? Search www.dejanews.com first!
-- There are no facts, only opinions --

by jw » Mon, 22 Jun 1998 04:00:00

>>> Ian cracked the ice around my prison with these words:

>>>> A strange request perhaps, but I want to test the softdog watchdog
>>>> facility, so I need to crash my 2.0.34 box, but can't think of a
>>>> way to do this. Does anyone know of a way? I know that a software
>>>> watchdog can fail to reboot a locked machine, but I want to see if
>>>> I can provoke it into action.

>>> As root: kill -9 1

>> That's more a case of nothing running rather than a crash, but it's a
>> definite start, I'll have a go. Annoyed I didn't think of it myself in
>> fact..

>Hmm, as it happens, this doesn't work. Anything but -INT has no effect
>on init, using -INT causes a clean reboot, exactly as if I'd typed
>"reboot".

>Does anyone else have any ideas??

There is a program called crashme, which executes random blocks of
data to check if all illegal opcodes are handled correctly. This will
cause most systems to crash eventually.

http://ftpsearch.unit.no will find it for you!

Else, type something like vi
/usr/src/linux/system/vm_critical_functions.c and invite your 4 year
old cousin to the keyboard, leave the room for 5 minutes and recompile
2> /dev/null :-)

Greetings,
Jurriaan
"It was the Law of the Sea, they said. Civilization ends at the waterline.
Beyond that, we all enter the food chain, and not always right at the top."
Hunter S. Thompson

by **Svei** » Mon, 22 Jun 1998 04:00:00

Quote:>A strange request perhaps, but I want to test the softdog watchdog
>facility, so I need to crash my 2.0.34 box, but can't think of a way
>to do this. Does anyone know of a way? I know that a software watchdog
>can fail to reboot a locked machine, but I want to see if I can
>provoke it into action.

doing,as root, kill -9 -1 will surely crash your computer in a flash..
Getting it up on software watchdog will of course not be guaranteed
though.
Killing vital processes can be a bit more controlled, but if this
states as a "crash" or not, I don't know.. Might be worth a try.
Svein

by Ia » Tue, 23 Jun 1998 04:00:00

Quote:> doing,as root, kill -9 -1 will surely crash your computer in a flash..
> Getting it up on software watchdog will of course not be guaranteed
> though.
> Killing vital processes can be a bit more controlled, but if this
> states as a "crash" or not, I don't know.. Might be worth a try.
> Svein

Killing processes will only kill other processes, if that. Using up
all the memory isn't likely to have any effect either other than to
kill off other programs, but locking the system seems to be pretty
hard. In fact, now I think about it harder it's quite difficult to
find any area where the software watchdog will actually be any use as
a kernel crash would prevent the watchdog file being written to, and
prevent the system from rebooting itself. I think I'll get a hardware
watchdog if I think it's worth the cash.

Does anyone know of any likely situations where the softdog will be of
any use, or am I wasting my time?

--
Ian - Edit address before mailing. | Have you got a question you want to ask
Running Linux in the UK. | Usenet? Search www.dejanews.com first!
-- There are no facts, only opinions --

by **vacu** » Fri, 26 Jun 1998 04:00:00

Quote:> A strange request perhaps, but I want to test the softdog watchdog
> facility, so I need to crash my 2.0.34 box, but can't think of a way
> to do this. Does anyone know of a way? I know that a software watchdog
> can fail to reboot a locked machine, but I want to see if I can
> provoke it into action.

On a fresh RH5.0 install i entered: vi [return], forgetting to include
the
[filename]. It locked up the whole machine solid (not just one
console).
I was impressed . . .

Quote:
> --
> Ian - Edit address before mailing. | Have you got a question you want to ask
> Running Linux in the UK. | Usenet? Search www.dejanews.com first!
> -- There are no facts, only opinions --

Vacuo
-. ..--- -.- --.- .-

by **Thomas L. Gossar** » Sat, 27 Jun 1998 04:00:00

Ian,

I agree, strange request. There is a sure way to crash the system. Move all
the libs in the various lib directories untill you find one that is being
used by init. I did this once by trying to install a lib that should have
been installed while in single user mode. The system hung big time.
I can't remember which lib it was, it was either in /lib or /usr/lib.

Before trying this though I would make a boot disk so you can fix the
problem after or the system may not boot again. If you take away a lib
the system uses to boot with and run you'll be in serious trouble if
you can't fix afterward.

Tom Gossard

------------------------

Subject: How can I crash my 2.0.34 box?
Date: 20 Jun 1998 15:52:21 GMT
rg.uk

Quote:> A strange request perhaps, but I want to test the softdog watchdog
> facility, so I need to crash my 2.0.34 box, but can't think of a way
> to do this. Does anyone know of a way? I know that a software watchdog
> can fail to reboot a locked machine, but I want to see if I can
> provoke it into action.

> --
> Ian - Edit address before mailing. | Have you got a question you want to ask
> Running Linux in the UK. | Usenet? Search www.dejanews.com first!
> -- There are no facts, only opinions --

---------------End of Original Message-----------------

--------------------------------------------------------
Name: Thomas L. Gossard

Date: 06/26/98
Time: 11:56:56

~ ~

oOOo-(_)-oOOo
--------------------------------------------------------

by **Mischa Sumral** » Sun, 28 Jun 1998 04:00:00

A few easy ways to crash 2.0.30, has 34 fixed these or are they
independent of the kernel? I can't remember exactly how, but Workman (X
based CD player) crashed my system - total lock-up, ctrl-alt-bksc and
ctrl-alt-del ineffective. I think I moved the rc and database files
while it was playing a CD.
Try to mount an unformatted HD partition.

> Ian,

> I agree, strange request. There is a sure way to crash the system.

by **Marc MERL** » Sat, 04 Jul 1998 04:00:00

>> A strange request perhaps, but I want to test the softdog watchdog
>> facility, so I need to crash my 2.0.34 box, but can't think of a way
>> to do this. Does anyone know of a way? I know that a software watchdog
>> can fail to reboot a locked machine, but I want to see if I can
>> provoke it into action.

>On a fresh RH5.0 install i entered: vi [return], forgetting to include
>the
>[filename]. It locked up the whole machine solid (not just one
>console).
>I was impressed . . .

The crash is not linked to your forgetting to type the filename. Your
machine just happened to crash at the same time for some other unknown
reason.

Marc
--
Home page: http://magic.metawire.com/~merlin/ (browser friendly)

by **Arthur Corli** » Mon, 06 Jul 1998 04:00:00

>>On a fresh RH5.0 install i entered: vi [return], forgetting to include
>>the
>>[filename]. It locked up the whole machine solid (not just one
>>console).
>>I was impressed . . .

>The crash is not linked to your forgetting to type the filename. Your
>machine just happened to crash at the same time for some other unknown
>reason.

>Marc
>--
>Home page: http://magic.metawire.com/~merlin/ (browser friendly)

You could also add that unless he tried accessing the box from the network,
it probably wasn't locked up solid.

--Arthur Corliss
"Live Free or Die--the Only Way to Live" (NH State Motto)