Documentation

Checks the aggregates or volumes interpolated usage-trend.

The art of prophecy is very difficult, especially with respect to the future. (Mark Twain)

This plugin warns that the aggregate or volume would be full within a given time, if the present trend would continue.

The --lookbehind-period must be configured in accordance with the collectors --stm (short-term-memory). The optional switch --tolerance may be usefull to relax the periods.

What is considered to be "full" can be defined with --full. This may be useful if you are expecting difficulties at already 95% or in case you want to overcommit an aggregate (>100%).

This check will return UNKNOWN until it finds enough history. So be patient and consider disabling the notifications until you get the first OK.

A trend of 0 or less is always considered to be ok.

Consider using -v for inspection, if you are not satisfied with the result.

Collecting History

This check requires a longer short-term-memory (history) about the past to be able to interpolate these historical trends into the future. Do not forget to set an appropriate value for the short-term-memory (--stm) in the corresponding getter for the volume and aggregate object. E.g. for a --lookbehind=1d the volume and aggregate getter needs a --stm=1d or even better --stm=25h.

Handling of too less history

If the getter did not collect enough history so far to fullfill the lookbehind the check tries with reduced lookbehind-values until lookbehind is getting smaller than tolerance + 10 seconds. If the check finds a value while trying it will return that value together with a hint and exit at least with a WARNING.

Checking inodes

Per default this plugin measures and interpolates the size in Bytes. Using --what=inodes this can be changed to inodes (files-used, files-total).