Linux and UNIX Man Pages

Linux & Unix Commands - Search Man Pages

wd_keepalive(8) [debian man page]

WD_KEEPALIVE(8) 					      System Manager's Manual						   WD_KEEPALIVE(8)

NAME
wd_keepalive - a simplified software watchdog daemon SYNOPSIS
wd_keepalive [-c filename|--config-file filename] DESCRIPTION
This is a simplified version of the watchdog daemon. If configured so it only opens .IR /dev/watchdog , and keeps writing to it often enough to keep the kernel from resetting, at least once per minute. Each write delays the reboot time another minute. After a minute of inactivity the watchdog hardware will cause a reset. In the case of the software watchdog the ability to reboot will depend on the state of the machines and interrupts. The wd_keepalive daemon can be stopped without causing a reboot if the device /dev/watchdog is closed correctly, unless your kernel is com- piled with the CONFIG_WATCHDOG_NOWAYOUT option enabled. Under high system load wd_keepalive might be swapped out of memory and may fail to make it back in in time. Under these circumstances the Linux kernel will reset the machine. To make sure you won't get unnecessary reboots make sure you have the variable realtime set to yes in the configuration file watchdog.conf. This adds real time support to wd_keepalive: it will lock itself into memory and there should be no problem even under the highest of loads. On system running out of memory the kernel will try to free enough memory by killing process. The wd_keepalive daemon itself is exempted from this so-called out-of-memory killer. OPTIONS
Available command line options are the following: -c config-file, --config-file config-file Use config-file as the configuration file instead of the default /etc/watchdog.conf. FILES
/dev/watchdog The watchdog device. /var/run/wd_keepalive.pid The pid file of the running wd_keepalive. SEE ALSO
watchdog.conf(5) watchdog(8) 4th Berkeley Distribution January 2005 WD_KEEPALIVE(8)

Check Out this Related Man Page

WATCHDOG(9)						   BSD Kernel Developer's Manual					       WATCHDOG(9)

NAME
watchdog -- software and hardware watchdog facility SYNOPSIS
#include <sys/watchdog.h> void watchdog_fn(void *private, u_int cmd, int *error); EVENTHANDLER_REGISTER(watchdog_list, watchdog_fn, private, 0); EVENTHANDLER_DEREGISTER(watchdog_list, eventhandler_tag); DESCRIPTION
To implement a watchdog in software or hardware, only a single function needs to be written and registered on the global watchdog_list. The function must examine the cmd argument and act on it as follows: If cmd is zero, the watchdog must be disabled and the error argument left untouched. If the watchdog cannot be disabled, the error argument must be set to EOPNOTSUPP. Else the watchdog should be reset and configured to a timeout of (1 << (cmd & WD_INTERVAL)) nanoseconds or larger and the error argument be set to zero to signal arming of a watchdog. If the watchdog cannot be configured to the proposed timeout, it must be disabled and the error argument left as is (to avoid hiding the arm- ing of another watchdog). There is no specification of what the watchdog should do when it times out, but a hardware reset or similar ``drastic but certain'' behaviour is recommended. SEE ALSO
watchdog(4) AUTHORS
The watchdog facility and this manual page was written Poul-Henning Kamp <phk@FreeBSD.org>. BSD
February 28, 2004 BSD
Man Page

10 More Discussions You Might Find Interesting

1. AIX

crontab displays power fail

Hi, My system has added an entry to the cron: --> crontab -l 0 00,12 * * * wall%rc.powerfail:2::WARNING!!! The system is now operating with a power problem. This message will be walled every 12 hours. Remove this crontab entry after the problem is resolved. I have had an issue... (8 Replies)
Discussion started by: chlawren
8 Replies

2. Solaris

disabling watchdog

hi, is it possible to disable the "hardware watchdog" on a V240 sol 10 server? and how to? this server freeze 9/10 during boot on this command...:mad: thanks (3 Replies)
Discussion started by: guilik
3 Replies

3. Solaris

T2000 ALOM reset to OBP

Every time I would try to send a break to my T2000 I would get this Debugging requested; hardware watchdog suspended. c)ontinue, s)ync, r)eset? I couldn't get into OBP. Here's what I found to do... sc> bootmode Bootmode: normal sc> bootmode reset_nvram sc> bootmode... (3 Replies)
Discussion started by: mediis
3 Replies

4. Linux

Modprobe problem

I'm trying to get a watchdog module working on a server. (Watchdog timers are little hardware devices that reboot the system if it becomes unresponsive.) The module takes some options like the timeout til reboot, what power action to take, etc. I've set these options up in... (4 Replies)
Discussion started by: vertigo23
4 Replies

5. Solaris

doubt reg Hardware watchdog enabled

Hi, Please let me know what is hardware watchdog enabled which we get when the solaris host is booting .As per my knowledge its the one states that the POST is enabled. correct me if am wrong. (1 Reply)
Discussion started by: rogerben
1 Replies

6. AIX

no watchdog notification

Hi All, I am getting pages from EMS(Event Monitoring Servers) for "no watchdog notification" I just wonder what cause this and what to look in the system. this error was generated from production lpar which hosts p570 Thanks Mann (4 Replies)
Discussion started by: chubby362002
4 Replies

7. UNIX for Advanced & Expert Users

Unix scripting

i need help with this problem this is the problem: Write a script that logs how many users login on/off the system over a 5 minute period. It can run in the foreground, and run 4 times a minute. Set a trap that will not allow a CNTRL-C command, and if a CNTRL-C is excuted store the time and date... (1 Reply)
Discussion started by: sportsmansixty6
1 Replies

8. SCO

System Clock running at half speed

SCO Openserver 6.0.0 had an issue with a NIC losing it's config on reboot. Netconfig would not allow "view protocol" and apparently zeroed out the existing IP info. Repaired from console. After this event, however, the system clock seems to lose 30 seconds for every RTC minute that passes. As a... (1 Reply)
Discussion started by: DoublePanic
1 Replies

9. Debian

Malicious perl script

Relative newbie to Linux so please be kind and assume I've done little in the way of command line but i have been thrusted into this position. Here goes. There is a perl script on my box that is using me as a mail server. It is contacting other mail servers to the point of slowing down the box.... (20 Replies)
Discussion started by: dadprpus
20 Replies

10. Solaris

T4-2 - Memory DIMM issue - ldom config resets to factory-default

Which basically means the ldoms that were on there are not starting (not even showing). If I do ldm list-config it shows live config as next reboot. But, of course, next reboot it reverts back to factory default again. I must admit I'm wondering if its doing this becasue (with the... (3 Replies)
Discussion started by: psychocandy
3 Replies

Featured Tech Videos