Does the Watchdog reboot log anything?

SteveITS

We have a client whose 3100 router rebooted on its own today, around 1:10 pm. We got an offline alert on their server saying its last contact was 13:08:20 (it checks in every 30 seconds).

Log entries have nothing between a 12:30 table update and the boot:

Sep 15 13:11:27 kernel Copyright (c) 1992-2021 The FreeBSD Project.
Sep 15 13:11:27 kernel ---<<BOOT>>---
Sep 15 13:11:27 syslogd kernel boot file is /boot/kernel/kernel
Sep 15 12:30:33 php 90035 rc.update_urltables: /etc/rc.update_urltables: [tablename] does not need updating.
Sep 15 12:30:33 php 90035 rc.update_urltables: /etc/rc.update_urltables: pfB_TOR_v4 does not need updating.

Does the watchdog feature log anything, or just trigger the boot? This happened before once, in April 2021 at 6:25 am.

SteveITS

I see it has a (small) RAM disk, guessing that'll lose anything that does get logged. Still is a good question to have answered... :)

stephenw10

That's a good question and the answer appears to be no.
If you kill -9 the watchdogd process it will reboot after the timeout expires without logging anything, which is expected. However unlike other watchdog hardware it also doesn't log anything at boot.
You might expect to see something like this when the driver attaches:

Sep 8 00:56:28 	kernel 		amdsbwd0: Previous Reset was caused by Watchdog
Sep 8 00:56:28 	kernel 		amdsbwd0: <AMD SB8xx/SB9xx/Axx Watchdog Timer> at iomem 0xfec000f0-0xfec000f3,0xfec000f4-0xfec000f7 on isa0

I don't see anything logged on the 3100. Or in the sysctls. Let me see if I can find anything...

Steve

SteveITS

@stephenw10 Not critical enough to stay up at 1am. :) The only log entry for "watchdog" is this which I assume is normal boot noise:

Sep 15 13:11:27 	kernel 		pmsu0: <Power Management Service Unit> mem 0x22000-0x22fff on simplebus1
Sep 15 13:11:27 	kernel 		wdt0: <Marvell **Watchdog** Timer> mem 0x20300-0x20333,0x20704-0x20707,0x18260-0x18263 irq 24,25 on simplebus1
Sep 15 13:11:27 	kernel 		gpioc1: <GPIO controller> on gpio1

Zero entries on the Watchdog log tab.

stephenw10

Yes, that's it attaching normally.