Polling definitions describe what will be polled when a collector is running, and how it will be presented. In the first release of real-time charts, polling definitions are imported/exported via opcharts-cli and can be viewed in the GUI.
opCharts ships with several polling definitions that may be useful and can be used as a guide when creating new ones. These files can be found in omk/install/nmisd/pollers.d/
Polling definitions must define their name (which must be unique) and can optionally have a description. There are 5 main sections in a polling definition (see below).
Changing a polling definition is not currently supported, if you need to do this please create a new poller with a new name and start collectors using the new poller.
Adding/Importing, Exporting, Removing
To add/import new polling definitions use opcharts-cli.pl, specify the file to get the definition from and if the file has more than one, specify the name of the poller to import:
Exporting takes the current poller definition and writes it to the file specified (or to the screen if no file is given):
Removing a poller requires that no collectors exist that use it (enabled or not). After all the collectors that use the poller have been removed, delete the poller like this:
- Graph options - set graph attributes (like axis titles, min/max).
- Properties - values that generally don't change over time but are needed to calculate a field or just presented with the graph.
- Virtual Properties - definitions of new variables which can be calculations using properties, other virtual properties and collector parameters.
- Fields - values that will be polled every time the collector runs.
- Virtual Fields - definitions of new variables which can be calculations using fields, properties, virtual properties and collector parameters.
The following are options that can be set:
Common attributes (Properties & Fields)
Properties and Fields define data that will be polled, because of this their definitions share common attributes. The following attributes are common to both:
Common attributes (Virtual Properties & Virtual Fields)
Virtual sections all run through the same parsing system so their definitions are similar, see the opCharts Resource Model Description Virtual Options section for more information.
The differences between property and field definitions is largely the data that is available to them when running calculations.
In addition to the common property/field attributes, properties can/must have the following attributes:
In addition to the common property/field attributes, fields can/must have the following attributes:
Here is an example to help make the definition clearer: