software watchdog

Jan Houstek jan.houstek na mff.cuni.cz
Pátek Prosinec 3 03:07:05 CET 2004


On Fri, 3 Dec 2004, Petr Vileta wrote:

> Hmm to me zajima. To je od jake verze kernelu? A kde najit neco blizsiho
> jak s tim zachazet, krome studia zdrojaku jadra? Neco jsem vygoogloval a
> dokonce pry to pouziva CMOS a BIOSovy alarm.
> http://freebooks.by.ru/view/RedHatLinux6Unleashed/rhl6u269.htm Mnooo, ze
> by to opravdu umely vsechny boardy? Znacna cast CMOS je ne/malo
> dokumentovana :-(

Ze vam to neni blby se ptat na neco, co je uplne na dosah ruky. Napr. v
helpu ke kernelu (k dostatni napr. skrze make menuconfig) se u polozky
CONFIG_WATCHDOG doctete:

"If you say Y here (and to one of the following options) and create a
 character special file /dev/watchdog with major number 10 and minor
 number 130 using mknod ("man mknod"), you will get a watchdog, i.e.:
 subsequently opening the file and then failing to write to it for
 longer than 1 minute will result in rebooting the machine. This
 could be useful for a networked machine that needs to come back
 online as fast as possible after a lock-up. There's both a watchdog
 implementation entirely in software (which can sometimes fail to
 reboot the machine) and a driver for hardware watchdog boards, which
 are more robust and can also keep track of the temperature inside
 your computer. For details, read Documentation/watchdog.txt
 in the kernel source.

 The watchdog is usually used together with the watchdog daemon
 which is available from
 <ftp://ibiblio.org/pub/Linux/system/daemons/watchdog/>. This daemon can
 also monitor NFS connections and can reboot the machine when the proces
 table is full."

Dalsi informace se doctete ve zminenem Documentation/watchdog.txt a v
dokumentaci k watchdog demononovi.

-- Honza Houstek


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