NAME¶
downtimed - system downtime monitoring and reporting daemon
SYNOPSIS¶
downtimed [
-D] [
-d datadir] [
-l log]
[
-p pidfile] [
-S] [
-s sleep]
downtimed -v
DESCRIPTION¶
The
downtimed daemon waits in the background, frequently updating a time
stamp file on the disk. If the daemon is killed with a signal associated with
a normal system shutdown procedure, it will record the shutdown time on the
disk.
When the daemon is restarted during the next boot process, it will report how
long the system was down and whether it was properly shut down or crashed. The
downtime report is output to the system log or to a specified log file. Also a
record is appended to the downtime database.
OPTIONS¶
- -D
- Do not create nor update the downtime database.
- -d datadir
- The directory where the time stamp files as well as the
downtime database are located. The default directory is determined at
compile time.
- -l log
- Logging destination. If the argument contains a slash (/)
it is interpreted to be a path name to a log file, which will be created
if it does not exist already. Otherwise it is interpreted as a syslog
facility name. The default logging destination is "daemon" which
means that the messages are written to syslog with the daemon facility
code.
- -p pidfile
- The location of the file which keeps track of the process
ID of the running daemon process. The system default location is
determined at compile time.
- -S
- Normally fsync(2) is performed after each update of
the time stamp. This option disables the fsync(2). It reduces the
load on the disk system but makes the downtime measurement less reliable.
This option is not available on all systems.
- -s sleep
- Defines how long to sleep between each update of the
on-disk time stamp file. More frequent updates result in more accurate
downtime reporting in the case of a system crash. Less frequent updates
decrease the amount of disk writes performed. The default is to sleep 15
seconds between eacch update. If you are using a flash memory based SSD or
other disk which has limited amount of write cycles per block, it might be
a good idea to set the sleep time to a higher value to prolong the
lifetime of the storage device.
- -v
- Display the program version number, copyright message and
the default settings.
SIGNALS¶
- SIGHUP
- Close and re-open the output log. Use in case you want to
rotate the log file.
- SIGTERM and SIGINT
- Terminate gracefully. These signals signify that a graceful
system shutdown is in process.
EXIT STATUS¶
The daemon exits 0 on success, and >0 if an error occurs.
SEE ALSO¶
downtimes(1),
syslog.conf(5), pdfhref
http://dist.epipe.com/downtimed/
BUGS¶
The reporting accuracy in case of a system crash depends on how often the time
stamp is updated.
Finding out the system startup time is very operating system specific. If the
program does not have specific code to support your operating system, it
assumes that the system started when the daemon started.
Reporting is inaccurate if the system clock changes during system downtime or
startup process. Daylight saving time changes have no effect as all
calculations are done using UTC.
COPYRIGHT¶
Copyright © 2009-2011 EPIPE Communications. All rights reserved.
Redistribution and use in source and binary forms, with or without modification,
are permitted provided that the following conditions are met:
1. Redistributions of source code must retain the above copyright notice, this
list of conditions and the following disclaimer.
2. Redistributions in binary form must reproduce the above copyright notice,
this list of conditions and the following disclaimer in the documentation
and/or other materials provided with the distribution.
THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND ANY
EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR ANY
DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
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(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
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