2. EL 8
  3. watchdog
  4. watchdog.conf(5)

Scroll to navigation

WATCHDOG.CONF(5) File Formats Manual WATCHDOG.CONF(5)

NAME

watchdog.conf - configuration file for the watchdog daemon

DESCRIPTION

This file carries all configuration options for the Linux watchdog daemon. Each option has to be written on a line for itself. Comments start with '#'. Blanks are ignored except after the '=' sign. An empty text after the '=' sign disables the feature as long as that makes sense.

OPTIONS

Set the highest possible interval between two writes to the watchdog device. The device is triggered after each check regardless of the time it took. After finishing all checks watchdog goes to sleep for a full cycle of <interval> seconds. Default value is 1 second. The kernel drivers typically expects a write command every minute otherwise the system will be rebooted. Therefore an interval of more than a minute can only be used with the force command-line option [--force | -f].
If you enable verbose logging, a message is written into the syslog or a logfile. While this is nice, it is not necessary to get a message every interval which really fills up disk and needs CPU. logtick allows adjustment of the number of intervals skipped before a log message is written. If you use logtick = 60 and interval = 10, only every 10 minutes (600 seconds) a message is written. This may make the exact time of a crash harder to find but greatly reduces disk usage and administrator nerves if you're looking for a particular syslog entry in between of watchdog messages.
Set the maximal allowed load average for a 1 minute span. Once this load average is reached the system is rebooted. Default value is 0. That means the load average check is disabled. Be careful not to set this parameter too low. To set a value less then the predefined minimal value of 2, you have to use the -f command line option.
Set the maximal allowed load average for a 5 minute span. Once this load average is reached the system is rebooted. Default value is 3/4*max-load-1. Be careful not to this parameter too low. To set a value less then the predefined minimal value of 2, you have to use the -f command line option.
Set the maximal allowed load average for a 15 minute span. Once this load average is reached the system is rebooted. Default value is 1/2*max-load-1. Be careful not to this parameter too low. To set a value less then the predefined minimal value of 2, you have to use the -f command line option.
Set the minimal amount of virtual memory that has to stay free. Note that this is in memory pages (4kB on x86). Default value is 0 pages which means this test is disabled. The page size is taken from the system include files. The usable memory is computed from MemFree + Buffers + Cached since buffer and cache use typically expand to use most free memory but the kernel will reclaim this as needed. NOTE: If this measure gets below a few tens of MB then the system will page swap aggressively have poorer file system performance due to the lack of caching. This is a 'passive' test and works by reading /proc/meminfo
Set the minimum amount of allocatable memory available on the system. Note that this is in pages. Default value is 0 pages which means the test is disabled. As with min-memory, the page size is taken from the system include files. This is an 'active' test and it works by attempting to memory-map a block of the configured size.
Set the maximum amount of swap use. Note that this is in memory pages (4kB on x86). Default value is 0 pages which means this test is disabled. Often this should be a large portion of available swap, but remember that paging 1GB of swap can take several/tens of seconds. This is a 'passive' test and works by reading /proc/meminfo
Set the watchdog device name, typically /dev/watchdog. Default is to disable keep alive support. This should be tested by running the daemon from the command line before configuring it to start automatically on booting.
Refresh watchdog timer by setting its timeout instead of using a normal watchdog refresh operation. Might help if your watchdog trips by itself when the first timeout interval elapses. Default is 'auto' for IT87 fix-up but this can be disabled with 'no' or forced for other modules with 'yes'.
Ignore errors reported by writing to the watchdog device. Typically this is used for systems that have broken implementations of the IPMI driver to avoid a reboot loop.
Set the watchdog device timeout during startup. If not set, a default is used that should be set to the kernel timer margin at compile time.
Set the temperature sensor name. This is normally a 'virtual file' under /sys and it contains the temperature in milli-Celsius. Usually these are generated by the sensors package, but take care as device enumeration may not be fixed. Default is to disable temperature checking. Multiple sensors can be used by having repeated temperature-sensor entries. Due to the enumeration problem any missing temp sensor is simply ignored and not treated as a reboot trigger.
Set the maximal allowed temperature in Celsius. Once this temperature is reached the system is stopped. Default value is 90 C. Watchdog will issue warnings once the temperature increases 90%, 95% and 98% of this temperature.
Set the watchdog action on overheating. Yes option (default) is to power the machine off, no option is to halt machine and allow Ctrl-Alt-Del reboot.
Set file name for file mode. This option can be given as often as you like to check several files.
Set the change interval time for file mode. This options always belongs to the active filename, that is when finding a 'change =' line watchdog assumes it belongs to the most recently read 'file =' line. They don't necessarily have to follow each other directly. But you cannot specify a 'change =' before a 'file ='. The default is to only stat the file and don't look for changes. Using this feature to monitor changes in /var/log/messages might require some special syslog daemon configuration, e.g. rsyslog needs "$ActionWriteAllMarkMessages on" to be set to make sure the marks are written no matter what.
Set pidfile name for daemon test mode. This option can be given as often as you like to check several daemons, assuming they write their post-forking PID to the specified files. See the Systemd section in watchdog (8) for more information.
Set IPv4 address for ping mode. This option can be used more than once to check different connections.
Set the number of ping attempts in each 'interval' of time. Default is 3 and it completes on the first successful ping.
Set interface name for network mode. This option can be used more than once to check different interfaces. Note it is only possible to check physical interfaces, and not aliased IP interfaces.
Execute the given binary to do some user defined tests. With enforcing SELinux policy please use the /usr/libexec/watchdog/scripts/ for your test-binary configuration.
User defined tests may only run for <timeout> seconds. Set to 0 for unlimited.
Execute the given binary in case of a problem instead of shutting down the system. With enforcing SELinux policy please use the /usr/libexec/watchdog/scripts/ for your repair-binary configuration.
repair command may only run for <timeout> seconds. Set to 0 for 'unlimited', but note that the hardware timer is not refreshed in this case so the system will hard-reset at some point.
Allow most error conditions to persist for <timeout> seconds. Set to 0 for immediate action (like softboot behaviour).
This allows no more then <count> repair attempts against a given fault that report success (i.e. return 0), but fail to clear the fault, before a reboot is initiated anyway. If set to zero then a repairable fault can always be blocked by a repair program reporting success (previous daemon behaviour).
This acts like the -b / --softboot command line and simply sets the retry timeout to zero.
Email address to send admin mail to. That is, who shall be notified that the machine is being halted or rebooted. Default is 'root'. If you want to disable notification via email just set admin to en empty string.
If set to yes watchdog will lock itself into memory so it is never swapped out.
Set the schedule priority for realtime mode passed to sched_setscheduler().
Set the directory to run user test/repair scripts. Default is '/etc/watchdog.d' The /etc/watchdog.d/ is recognized by SELinux policy. See the Test Directory section in watchdog(8) for more information.
Set the log directory to capture the standard output and standard error from repair-binary and test-binary execution. Default is '/var/log/watchdog'.
Set the time on shut down between first sending SIGTERM to all processes, and then sending SIGKILL. Default is 5 seconds which is generally enough, but systems with large databases or virtual machines might need longer.
This overrides the command line --verbose option. Generally the verbose mode is only enabled for debugging as it creates a lot of syslog chatter, so use this option with consideration.

FILES

/etc/watchdog.conf
The watchdog configuration file
/etc/watchdog.d
A directory containing test-or-repair commands. See the Test Directory section in watchdog(8) for more information.

SEE ALSO

watchdog(8)

February 2019 4th Berkeley Distribution