downtimed - system downtime monitoring and reporting tool
Copyright (c) 2009-2016 Janne Snabb. All rights reserved.
This software is licensed under the terms and conditions of the Simplified BSD License. You should have received a copy of that license along with this software.
Software web site:
Development version is available at GitHub:
Use GitHub for reporting bugs, sending contributions etc.
Compatible operating systems / distributions:
- FreeBSD, NetBSD and OpenBSD
- Mac OS X/Darwin
- Solaris / OpenSolaris / OpenIndiana
The only really non-portable part of the program is the getboottime() function which uses an operating system specific interface for finding the exact moment when the kernel started again. The function can be easily altered to add support for additional operating systems. The author would appreciate receiving any such patches to be integrated in the main distribution.
Also for the sake of convenience the program uses some functions which are available only in modern operating systems. These include for example asprintf(3), vasprintf(3), snprintf(3), err(3) and errx(3).
The author of this software had a Xen based virtual private server (VPS) running FreeBSD operating system. Occasionally the owner of the physical non-virtual machine would turn off the VPS to do some system administration tasks on the host operating system, which the author did not have access to. The author wanted to have some sort of record of when, why and how long the VPS had been down. The standard FreeBSD system did not provide such a facility.
After some looking around it seemed that there was only programs for monitoring uptime but not downtime. Also most of these programs were complicated and were intended to be run on a remote host and thus they would be actually monitoring the system availability through the network instead of the actual downtime of the FreeBSD operating system running on the VPS. Also they would require an another server for monitoring the primary server.
Therefore downtimed was needed.
downtimed was made to monitor operating system downtime, shutdowns and crashes on the monitored host itself and to keep a record of such events.
downtimed(8) is a daemon process which is intended to be started automatically from system boot scripts every time when the operating system of a server starts. First the daemon logs its findings about the previous downtime to a specified logging destination as well as in a database file which can be displayed with downtimes(1) command.
Thereafter the downtimed(8) daemon just keeps waiting in the background and periodically updates a time stamp file on the disk. The time stamp is used to determine the approximate time when the system was last up and running. In case of a graceful system shutdown it records a stamp to another file on the disk. These files are used for reporting the next time the daemon starts.
downtimes(1) is a command-line tool which can be used to inspect previous downtime records recorded in the downtime database file.
Installation should be preferably done through a port or a package which is tailored to your specific operating system.
If one does not exist or if you yourself are making such a port or a package, the basic GNU autotools based installation should be as follows:
./configure make make install
The above does NOT install any startup scripts which are REQUIRED for proper function of downtimed. See the following chapter.
The program also needs a persistent data directory for the time stamp and the downtime database files. It should be created on *BSD and MacOS X as follows:
...or on GNU/Linux, Debian GNU/kFreeBSD, GNU/Hurd or Solaris as follows:
Note that you can determine the default data directory location on
your system by issuing
downtimed -v command or you can specify a
different directory with the
-d option. Set the directory permissions
as appropriate in your environment. If you are installing a port or
package tailored for your system, this step is most likely taken care
for you automatically.
It seems that every different operating system and distribution has invented their own ways of starting system daemons during the boot process. That is a major pain in the ass.
The downtimed distribution includes the following operating system and distribution specific startup script samples. They are located in the "startup-scripts" directory. It is assumed that system administrators or port/package maintainers will implement and configure the required startup scripts. They are not installed by default.
This program is not really useful unless there is a proper startup script in place. Refer to your operating system or distribution manual on how to create and manage daemon startup scripts.
systemd: Debian, Ubuntu, RHEL / CentOS
Debian 8, Ubuntu 15.04, RHEL / CentOS 7 and later versions are using systemd for managing system services.
systemd unit file is included as downtimed.service. It should be installed as /etc/systemd/system/downtimed.service. Issue the following commands as root to enable and start the service:
systemctl enable downtimed systemctl start downtimed
Arch Linux startup script is included as archlinux-startup.sh. It should be installed as /etc/rc.d/downtimed and added to the DAEMONS setting in /etc/rc.conf.
A sample startup script for FreeBSD is included as freebsd-startup.sh. It should be installed as /usr/local/etc/rc.d/downtimed.
downtimed_enable="YES" in one of the following files to enable boot time
startup: /etc/rc.conf /etc/rc.conf.local /etc/rc.conf.d/downtimed
Add the following if you want to configure downtimed(8) command line
downtimed_flags="<set as needed>"
Mac OS X
Mac OS X/Darwin launchd(8) configuration file com.epipe.downtimed.plist is also included. This file should be installed to /Library/LaunchDaemons.
OpenIndiana / OpenSolaris / Solaris
SMF (Service Management Facility) manifest for OpenIndiana, OpenSolaris and Solaris 10 & 11 is in downtimed.smf.xml. It is not usable on Solaris 9 and older as they need a SysV style init script instead.
A startup script for openSUSE is included as opensuse-startup.sh. It
should be installed as /etc/init.d/downtimed. Running the command
innserv /etc/init.d/downtimed enables starting the service at the
A startup script for GNU/Debian and related distributions with SysV style
init scripts is included as debian-startup.sh. It should be installed as
/etc/init.d/downtimed. Running the command
update-rc.d downtimed defaults
enables starting the service at the system startup.
Users of Debian 8 and later should look at the systemd instructions above.
old RHEL based distributions (CentOS, Scientific Linux, Oracle Linux)
A startup script for RHEL 5 and 6 and related distributions is included as
redhat-startup.sh. It should be installed as /etc/rc.d/init.d/downtimed.
Running the command
chkconfig --add downtimed enables starting the
service at the system startup.
Users of RHEL/CentOS 7 and later should look at the systemd instructions above.
A startup script for GNU/Linux distributions using upstart(8) to bring up system daemons, such as the Ubuntu distribution until version 14.10, is included in upstart-startup.conf. It should be installed as /etc/init/downtimed.conf.
Users of Ubuntu 15.04 and later should look at the systemd instructions above.
Have a look at downtimed(8) manual page:
... as well as the downtimes(1) manual page:
Alternatively you can find a PDF version of the manual pages at:
If you port this software to a new operating system, find bugs or implement new features, it would be nice if you could send your patches to the author either through Github or by e-mail. See the top of this document for contact information.
The following people have contributed patches or other improvements to this software:
- Mac OS X patches
Mats Erik Andersson
- OpenBSD, Debian GNU/kFreeBSD and other patches
- openSUSE startup script
- Arch Linux startup script
- FreeBSD 9 compatibility fix
Others who I may have forgotten. (Sorry!)