Check cometsystem


This check targets the JSON endpoint of a COMET SYSTEM Web Sensor. Cometsystem web sensors allow configuration of two separate alarms for each channel. The alarm mode selects the direction of the alarm - lower than limit, higher than limit or disabled. This check plugin allows you to define a severity for each channel and alarm mode.

The repeating --severity parameter can be set in different ways:

  • --severity ok|warn|crit|unknown: High and low alarm severity for all channels and all alarm modes.

  • --severity part-of-channel-name:ok|warn|crit|unknown: High and low alarm severity for a specific channel and all alarm modes. You just need to specify a part of the channel name. Case-insensitive.

  • --severity part-of-channel-name:low|high:ok|warn|crit|unknown: Alarm severity for a specific channel and a specific alarm mode.

The order of --severity matters, the first match wins.


./cometsystem --url --severity temp:high:crit --severity humi:ok --severity warn

Here, the check raises critical for any channel with „temp“ in its name on high alarms only, returns ok for any alarm in channels with „humi“ in their name, and finally warns on all other alarms in all other channels. The last --severity warn can be omitted as this is the default behavior.

Fact Sheet

Check Plugin Download

Check Interval Recommendation

Once a minute

Can be called without parameters


Compiled for

Linux, Windows


usage: cometsystem [-h] [-V] [--always-ok] [--insecure] [--no-proxy]
                   [--severity SEVERITY] [--test TEST] [--timeout TIMEOUT] -u

This check targets the JSON endpoint of Web

  -h, --help           show this help message and exit
  -V, --version        show program's version number and exit
  --always-ok          Always returns OK.
  --insecure           This option explicitly allows to perform "insecure" SSL
                       connections. Default: False
  --no-proxy           Do not use a proxy. Default: False
  --severity SEVERITY  Severity for alerting, order matters, first match on
                       part of a channel name wins. Have a look at the README
                       for details. Example: `--severity temp:high:crit
                       --severity dew:low:crit --severity humi:ok --severity
                       warn`. Repeating. Default: warn
  --test TEST          For unit tests. Needs "path-to-stdout-file,path-to-
  --timeout TIMEOUT    Network timeout in seconds. Default: 5 (seconds)
  -u URL, --url URL    Comet system URL pointing to the JSON file

Usage Examples

./cometsystem --url --severity temp:high:crit --severity dew:ok


There are critical errors on Web Sensor SN 17965562.

Ch# ! Name                 ! Alarm ! Value
ch1 ! Temperature          ! high  ! 27.3C [CRITICAL]
ch2 ! Relative humidity    !       ! 43.1%RH
ch3 ! Dew point            ! low   ! 13.7C
ch4 ! Atmospheric pressure !       ! 958.6hPa


  • WARN for any alarm threshold violations.

Perfdata / Metrics

Name of the channel and its value, depend on the Web Sensor model and its configuration. For example:




Atmospheric pressure

Number Barometric pressure or weight of the atmosphere above.

Dew point

Number Temperature at which condensation starts.

Relative humidity


Relative humidity.


Number Temperature in C or F.

Credits, License