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[](https://pypi.python.org/pypi/check_systemd)
[](https://travis-ci.org/Josef-Friedrich/check_systemd)
# check_systemd
`check_systemd` is a [Nagios](https://www.nagios.org) /
[Icinga](https://icinga.com) monitoring plugin to check
[systemd](https://systemd.io). This Python script will report a degraded
system to your monitoring solution. It can also be used to monitor
individual systemd services (with the `-u, --unit` parameter) and timers
units (with the `-t, --dead-timers` parameter). The only dependency the
plugin needs is the Python library
[nagiosplugin](https://nagiosplugin.readthedocs.io/en/stable).
## Installation
```
pip3 install check_systemd
```
## Packages
* Debian ([package](https://ftp-master.debian.org/new/monitoring-plugins-systemd_2.3.0+ds-1.html), [source code](https://salsa.debian.org/python-team/packages/monitoring-plugins-systemd/-/tree/debian/master/debian)): work in progress
* NixOS ([package](https://search.nixos.org/packages?channel=unstable&query=check_systemd), [source code](https://github.com/NixOS/nixpkgs/blob/nixos-unstable/pkgs/servers/monitoring/nagios/plugins/check_systemd.nix)): `nix-env -iA nixos.check_systemd`
## Command line interface
```
usage: check_systemd [-h] [-u UNIT | -e UNIT] [-n] [-w SECONDS] [-c SECONDS]
[-t] [-W SECONDS] [-C SECONDS] [-i] [-v] [-V]
Copyright (c) 2014-18 Andrea Briganti <kbytesys@gmail.com>
Copyright (c) 2019-21 Josef Friedrich <josef@friedrich.rocks>
Nagios / Icinga monitoring plugin to check systemd.
optional arguments:
-h, --help show this help message and exit
-u UNIT, --unit UNIT Name of the systemd unit that is being tested.
-e UNIT, --exclude UNIT
Exclude a systemd unit from the checks. This option can
be applied multiple times, for example: -e mnt-
data.mount -e task.service. Regular expressions can be
used to exclude multiple units at once, for example: -e
'user@\d+\.service'. For more informations see the
Python documentation about regular expressions
(https://docs.python.org/3/library/re.html).
-n, --no-startup-time
Don’t check the startup time. Using this option the
options '-w, --warning' and '-c, --critical' have no
effect. Performance data about the startup time is
collected, but no critical, warning etc. states are
triggered.
-w SECONDS, --warning SECONDS
Startup time in seconds to result in a warning status.
Thedefault is 60 seconds.
-c SECONDS, --critical SECONDS
Startup time in seconds to result in a critical status.
Thedefault is 120 seconds.
-t, --dead-timers Detect dead / inactive timers. See the corresponding
options '-W, --dead-timer-warning' and '-C, --dead-
timers-critical'. Dead timers are detected by parsing
the output of 'systemctl list-timers'. Dead timer rows
displaying 'n/a' in the NEXT and LEFTcolumns and the
time span in the column PASSED exceeds the values
specified with the options '-W, --dead-timer-warning'
and '-C, --dead-timers-critical'.
-W SECONDS, --dead-timers-warning SECONDS
Time ago in seconds for dead / inactive timers to
trigger a warning state (by default 6 days).
-C SECONDS, --dead-timers-critical SECONDS
Time ago in seconds for dead / inactive timers to
trigger a critical state (by default 7 days).
-i, --ignore-inactive-state
Ignore an inactive state on a specific unit. Oneshot
services for example are only active while running and
not enabled. The rest of the time they are inactive.
This option has only an affect if it is used with the
option -u.
-v, --verbose Increase output verbosity (use up to 3 times).
-V, --version show program's version number and exit
Performance data:
- count_units
- startup_time
- units_activating
- units_active
- units_failed
- units_inactive
```
## Project pages
* on [github.com](https://github.com/Josef-Friedrich/check_systemd)
* on [icinga.com](https://exchange.icinga.com/joseffriedrich/check_systemd)
* on [nagios.org](https://exchange.nagios.org/directory/Plugins/System-Metrics/Processes/check_systemd/details)
## Behind the scenes
To detect failed units this monitoring script runs:
```sh
systemctl list-units --all
```
To get the startup time it executes:
```sh
systemd-analyze
```
To check a specific unit (`-u, --unit`) this command is executed:
```sh
systemctl is-active <unit-name>
```
To find dead timers this plugin launches:
```sh
systemctl list-timers --all
```
To learn how `systemd` produces the text output on the command line, it
is worthwhile to take a look at `systemd`’s source
code. Files relevant for text output are:
[basic/time-util.c](https://github.com/systemd/systemd/blob/main/src/basic/time-util.c),
[analyze/analyze.c](https://github.com/systemd/systemd/blob/main/src/analyze/analyze.c).
## Testing
```
pyenv install 3.6.12
pyenv install 3.7.9
pyenv local 3.6.12 3.7.9
pip3 install tox
tox
```
## Deploying
Edit the version number in check_systemd.py (without `v`). Use the `-s`
option to sign the tag (required for the Debian package).
```
git tag -s v2.0.11
git push --tags
```
|
