Re: software watchdog

From: Oliver Xymoron (oxymoron@waste.org)
Date: Tue Dec 11 2001 - 13:48:19 EST


On Tue, 11 Dec 2001, Russell King wrote:

> On Tue, Dec 11, 2001 at 04:26:07PM +0530, gspujar@hss.hns.com wrote:
> > Why is that the printk output not going to syslog although I have entry in
> > /etc/syslog.conf
> >
> > kern.crit /var/log/pbsc.log
> > even after I remove the mdelay call.
>
> The machine reboots before syslog gets to run.
>
> What happens is:
>
> printk();
> reboot();
>
> During that period, syslog is unable to run, and therefore is unable to
> write the log message to disk.
>
> > Does it mean that without using "testing" mode ( I cannot beacuse I need a
> > reboot) it is not possible to get log ?
>
> I suppose you could modify softdog to delay the reboot using it's timer
> (the timer fires the first time, you check data to see if it's non-zero.
> If it's not, increment watchdog_ticktock.data, and set the watchdog to
> timeout in 5 seconds, return).

Silly. The whole point of watchdog is to reboot a wedged machine. The
reason it's firing is presumably because the userspace watchdog
daemon didn't get a chance to touch the device, so odds that syslog would
get a chance to run are pretty slim.

If you really need a log message, get a serial console.

-- 
 "Love the dolphins," she advised him. "Write by W.A.S.T.E.."

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