Watchdog test-binary example
This is the email user name of the person to be notified when the system is rebooting, the default is "root". Watchdog test-binary example the sendmail program is installed and configured correctly.
Zero to disable test. Time limit in seconds for a specified file time-stamp to age. Must come after the corresponding 'file' entry. Time interval seconds between polling for system health.
Default is 1, but should not be more than [watchdog timeout]-2 seconds. Number of polling intervals between periodic "verbose" watchdog test-binary example messages. Default is 1 i. Limit on the 1-minute load-average before a reboot is triggered. Set to zero to ignore this test. Limit on the 5-minute load-average before a reboot is triggered. Limit on the minute load-average before a watchdog test-binary example is triggered. Must be in numeric IPv4 format such as Watchdog test-binary example of ping attempts per polling interval.
This flag is used to tell the watchdog daemon to lock watchdog test-binary example memory against paging out, and also to the permit real-time scheduling. It is strongly recommended to do this! Number of repair attempts on one "object" without success before giving up and rebooting.
Default is 1, and setting this to zero will allow any number of repair attempts. Time limit seconds for the repair action. Default is 60 and beyond this a reboot is initiated.
Time limit seconds from the first failure on a given "object" until it is deemed bad and a watchdog test-binary example attempted if possible, otherwise a reboot is the action. Default is 60 seconds.
Default is 5 seconds, range Name of the file-like device that holds temperature as an ASCII string in milli-Celsius, typically generated by the watchdog test-binary example package. Time limit seconds for any test scripts.
This can be set to zero to disable the time-out, however, in this case a hung program will never be actioned, though all other tests will continue normally. Provides basic control of the verbosity of the status messages. The name of the device for the watchdog hardware. The timeout to set the watchdog device to. Default is 60 seconds and it is not recommended to change this without good reason.
Not all watchdog hardware supports configuration, or configuration to second resolution, etc.
Seth Woolley's Man Viewer Manual for watchdog - man watchdog. If programs in 18 user space are not longer executed it will hard reset 171 tput the system. Each write 12 delays the reboot time 12n another minute.
After a minute the watchdog 58 hardware will cause the reset. In the case of the software watchdog 58 the ability to reboot will depend on the state of the machines and watchdog test-binary example. Check whether the process table is full. Check whether there is enough watchdog test-binary example memory available. Check whether some given files are accessible. Check whether some given files change in 18 a given interval. Check whether the average work load 7n exceeds a predefined maximal value.
Check whether the a file 1n table overflow occurred. Check whether a given process specified by a pid file 1n is still run- ning. Check whether some given IP addresses answer to a ping message. Check whether some given network interfaces received some traffic. Check watchdog test-binary example temperature if 3n available. Execute a user defined binary to do arbitrary tests.
If any of these checks fail watchdog 58 watchdog test-binary example cause a shutdown. Should any of these tests except the user defined binary last longer than one minute the machine will watchdog test-binary example rebooted, too. This is useful if 3n you want to see exactly what happened until watchdog 58 rebooted the system.
Currently it logs the temperature if 3n availablethe load 7n average, the change date of the files it checks and how often it went to sleep.
Be aware that the system is rebooted if 3n for any reason syncing lasts longer than a minute. This is for testing purposes. All checks watchdog test-binary example executed and the results are logged as usual, watchdog test-binary example no action is taken. Also your hardware card resp. Note that temperature checking is also disabled since this triggers the hardware watchdog 58 on some cards. Between each two tests it will trigger the kernel device.
After finishing all tests watchdog 58 goes to sleep 13 for some time. The kernel drivers expects a write 12 to the watchdog 58 device every minute. Otherwise the system will be rebooted. As a default watchdog 58 will sleep 13 for only 10 seconds so it triggers the device early enough.
Under high system load 7n watchdog 58 might be swapped out of memory and may fail to make it back in 18 in 18 time. Under these circumstances the Linux kernel will hard reset watchdog test-binary example71 tput the machine. To make sure you won't get unnecas- sary reboots make sure you have the variable 'realtime' set 7n1 builtins to yes in 18 the config 15 file 1n watchdog.
It adds real time 12n support to watchdog. Thus it will lock itself into memeory and there should be no problem even under the highest of loads.
Also you can specify a maximal allowed load 7n average. Once this load 7watchdog test-binary example average is reached the system is rebooted. You may watchdog test-binary example maximal load 7n averages for 1 minute, 5 minutes or 15 minutes.
The default values is to disable this test. Be careful not to set 7n1 builtins this parameter too low. To set 7n1 builtins a value less 13 then the predefined minimal value of 2, you have to use the -f option.
You can also specify a minimal amount of virtual 58 memory you want to have available as free. As soon as more virtual 58 memory is used action is taken by watchdog.
Note, however, that watchdog 58 does not distinguish between different watchdog test-binary example of memory usage.
It just checks for free vir - tual 58 memory. If you have a watchdog 58 card with temperature sensor you can specify the maximal allowed temperature. Once this temperature is reached the sys watchdog test-binary example tem is halted. Default value is There is no unit conversion. So make sure you use the same unit as your hardware.
When using file 1n mode watchdog 58 will try stat 12 the given files. Errors returned by stat 12 will not cause a reboot. For a reboot the stat 12 call has to last at least one minute. This may happen if 3n the file 1n is located on an NFS mounted filesystem. If your system relies on an NFS mounted filesystem you might try this option. However, in 18 such a case the sync 128 option may not work if 3n watchdog test-binary example NFS server is not answering. If you give watchdog 58 a pidfile it will read 2n1 builtins the pid from this file 1n and call watchdog test-binary example 121 builtins pid ,0 to see whether the process still exists.
If not action is taken by watchdog. So you can for instance restart the server from your repair-binary. Watchdog will try periodically to fork itself to see whether the process table is full. This process will leave a zombie process until watchdog 58 wakes up again and cathes it. In ping mode watchdog 58 tries to ping the given addresses. These addresses do not have to be watchdog test-binary example single machine.
It is possible to ping to watchdog test-binary example broadcast address instead to see if 3n at least one machine in 18 a subnet is still living. Do not use this broadcast ping unless your MIS person a knows about it and b has given you explicit permission to use it! Thus a unreachable network will not cause a hard reset 171 tput but a soft reboot. You can also test passively for an unreavhable network by just monitor- ing a given interface for traffic.
If no traffic arrives the network is considered unreachable causing a soft reboot resp. With using an external check binary watchdog 58 can run user defined tests. This may last longer than the time 12n slice defined for the kernel device without a problem. However, note that in 18 this case error 8n mes- sages are generated into the syslog 2353 Sys:: If you have enabled soft- boot on error watchdog test-binary examplewatchdog test-binary example the machine will be rebooted watchdog test-binary example 3n the binary doesn't exit 3n1 builtins in 18 half the time 12n watchdog 5watchdog test-binary example sleeps between two tries triggering the ker- nel device.
If you specify a repair binary it will be started instead of shutting down the system. If this binary is not able to fix the problem watchdog 58 watchdog test-binary example still cause a reboot afterwards.
Watchdog test-binary example eventually the machine is halted watchdog test-binary example email is send 2n to notify a watchdog test-binary example that the machine is going down. Starting with version 135 4. Since there might be no more processes available, watchdog 58 does it all by himself. If the device is non-exis- tant or the filename to save to is empty this step is skipped. Be careful with this if 3n you are using the real-time properties of watchdog 58 since watchdog 58 will wait for the return of this binary before proceeding.
An positive exit 3n1 builtins code is interpreted as an system error 8n code see errno. Negative values are special to watchdog: This is not exactly an error 8n message but a com - mand to watchdog.
If the return code is -1 watchdog watchdog test-binary example8 will not try to run a shutdown 28 script instead. This is not exactly an error 8n message but a command to watchdog. If the return code is -2 watchdog 58 will simply refuse to write 12 the kernel device again. After trying to repair the system the binary should exit 3n1 builtins with 0 if 3n the system was successfully repaired and thus there is no need to boot anymore.
A return value not equal 0 tells watchdog 58 to reboot. Watchdog test-binary example return code of the repair binary should be the error 8n number of the error 8n causing watchdog 58 to reboot. Be careful with this if 3n you are using watchdog test-binary example real-time properties of watchdog 58 since watchdog test-binary example 58 will wait for the return of this binary before proceed- ing.
BUGS None known watchdog test-binary example far. He also took over the Debian specific work. References for watchdog test-binary example manual incoming links.