Mailing List Archive: Linux-HA: Pacemaker

about iTCO_wdt watchdog

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xiaozunvlg at gmail

Aug 1, 2012, 7:36 PM

Post #1 of 5 (602 views)
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about iTCO_wdt watchdog

Hi All:
I use IBM 3650 to build a HA cluster. And set iTCO_wdt as the
watchdog. The following test is performed
1. modprobe iTCO_wdt heartbeat=60 nowayout=1
2. echo "1" >/dev/watchdog
system will reboot after 60s

But when I run command echo "c" >/proc/sysrq-trigger after
echo "1" >/dev/watchdog. System will crash but can not reboot.

As I know, iTCO_wdt is a hardware driver, system will be reboot if
no data is writter in 60 seconds even when system crash. What's
wrong here?

_______________________________________________
Pacemaker mailing list: Pacemaker [at] oss
http://oss.clusterlabs.org/mailman/listinfo/pacemaker

Project Home: http://www.clusterlabs.org
Getting started: http://www.clusterlabs.org/doc/Cluster_from_Scratch.pdf
Bugs: http://bugs.clusterlabs.org

emi2fast at gmail

Aug 2, 2012, 12:09 AM

Post #2 of 5 (581 views)
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Re: about iTCO_wdt watchdog [In reply to]

echo "b" >/proc/sysrq-trigge

2012/8/2 Mia Lueng <xiaozunvlg [at] gmail>

> Hi All:
> I use IBM 3650 to build a HA cluster. And set iTCO_wdt as the
> watchdog. The following test is performed
> 1. modprobe iTCO_wdt heartbeat=60 nowayout=1
> 2. echo "1" >/dev/watchdog
> system will reboot after 60s
>
> But when I run command echo "c" >/proc/sysrq-trigger after
> echo "1" >/dev/watchdog. System will crash but can not reboot.
>
> As I know, iTCO_wdt is a hardware driver, system will be reboot if
> no data is writter in 60 seconds even when system crash. What's
> wrong here?
>
> _______________________________________________
> Pacemaker mailing list: Pacemaker [at] oss
> http://oss.clusterlabs.org/mailman/listinfo/pacemaker
>
> Project Home: http://www.clusterlabs.org
> Getting started: http://www.clusterlabs.org/doc/Cluster_from_Scratch.pdf
> Bugs: http://bugs.clusterlabs.org
>

--
esta es mi vida e me la vivo hasta que dios quiera

xiaozunvlg at gmail

Aug 2, 2012, 1:06 AM

Post #3 of 5 (585 views)
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Re: about iTCO_wdt watchdog [In reply to]

you misunderstand me. I just simulate a system crash to test if the
watchdog can reboot the system .

2012/8/2 emmanuel segura <emi2fast [at] gmail>:
> echo "b" >/proc/sysrq-trigge
>
> 2012/8/2 Mia Lueng <xiaozunvlg [at] gmail>
>>
>> Hi All:
>> I use IBM 3650 to build a HA cluster. And set iTCO_wdt as the
>> watchdog. The following test is performed
>> 1. modprobe iTCO_wdt heartbeat=60 nowayout=1
>> 2. echo "1" >/dev/watchdog
>> system will reboot after 60s
>>
>> But when I run command echo "c" >/proc/sysrq-trigger after
>> echo "1" >/dev/watchdog. System will crash but can not reboot.
>>
>> As I know, iTCO_wdt is a hardware driver, system will be reboot if
>> no data is writter in 60 seconds even when system crash. What's
>> wrong here?
>>
>> _______________________________________________
>> Pacemaker mailing list: Pacemaker [at] oss
>> http://oss.clusterlabs.org/mailman/listinfo/pacemaker
>>
>> Project Home: http://www.clusterlabs.org
>> Getting started: http://www.clusterlabs.org/doc/Cluster_from_Scratch.pdf
>> Bugs: http://bugs.clusterlabs.org
>
>
>
>
> --
> esta es mi vida e me la vivo hasta que dios quiera
>
> _______________________________________________
> Pacemaker mailing list: Pacemaker [at] oss
> http://oss.clusterlabs.org/mailman/listinfo/pacemaker
>
> Project Home: http://www.clusterlabs.org
> Getting started: http://www.clusterlabs.org/doc/Cluster_from_Scratch.pdf
> Bugs: http://bugs.clusterlabs.org
>

_______________________________________________
Pacemaker mailing list: Pacemaker [at] oss
http://oss.clusterlabs.org/mailman/listinfo/pacemaker

Project Home: http://www.clusterlabs.org
Getting started: http://www.clusterlabs.org/doc/Cluster_from_Scratch.pdf
Bugs: http://bugs.clusterlabs.org

vchepkov at gmail

Sep 9, 2012, 6:44 AM

Post #4 of 5 (498 views)
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Re: about iTCO_wdt watchdog [In reply to]

On Aug 2, 2012, at 4:06 AM, Mia Lueng wrote:

> you misunderstand me. I just simulate a system crash to test if the
> watchdog can reboot the system .
>

All kernel wdt modules still rely on a functioning kernel.
But you crashed kernel at this point, so no one will reboot your system.
What I think you want is to have watchdog enabled in the BIOS (if you have it) and then use some vendor program to support that real "hardware" watchdog. I think most of them are available via IPMI.

P.S. I think it's off-topic for this list though - you probably will get a better chance to get answer in linux-ha maillist.

Vadym

_______________________________________________
Pacemaker mailing list: Pacemaker [at] oss
http://oss.clusterlabs.org/mailman/listinfo/pacemaker

Project Home: http://www.clusterlabs.org
Getting started: http://www.clusterlabs.org/doc/Cluster_from_Scratch.pdf
Bugs: http://bugs.clusterlabs.org

lmb at suse

Sep 9, 2012, 12:51 PM

Post #5 of 5 (500 views)
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Re: about iTCO_wdt watchdog [In reply to]

On 2012-09-09T09:44:12, Vadym Chepkov <vchepkov [at] gmail> wrote:

> > you misunderstand me. I just simulate a system crash to test if the
> > watchdog can reboot the system .
> All kernel wdt modules still rely on a functioning kernel.

Actually, no, except for softdog, they do not.

TCO_wdt *is* a hardware-assisted watchdog, the hardware just happens to
be integrated in the CPU/motherboard.

Regards,
Lars

--
Architect Storage/HA
SUSE LINUX Products GmbH, GF: Jeff Hawn, Jennifer Guild, Felix Imend�rffer, HRB 21284 (AG N�rnberg)
"Experience is the name everyone gives to their mistakes." -- Oscar Wilde

_______________________________________________
Pacemaker mailing list: Pacemaker [at] oss
http://oss.clusterlabs.org/mailman/listinfo/pacemaker

Project Home: http://www.clusterlabs.org
Getting started: http://www.clusterlabs.org/doc/Cluster_from_Scratch.pdf
Bugs: http://bugs.clusterlabs.org

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