NAME

       rrdtune - Modify some basic properties of a Round Robin Database

SYNOPSIS

       rrdtool tune filename [--heartbeat|-h ds-name:heartbeat] [--minimum|-i ds-name:min]
       [--maximum|-a ds-name:max] [--data-source-type|-d ds-name:DST]
       [--data-source-rename|-r old-name:new-name] [--deltapos scale-value] [--deltaneg scale-
       value] [--failure-threshold failure-threshold] [--window-length window-length]
       [--alpha adaption-parameter] [--beta adaption-parameter] [--gamma adaption-parameter]
       [--gamma-deviation adaption-parameter] [--smoothing-window fraction-of-season]
       [--smoothing-window-deviation fraction-of-season] [--aberrant-reset ds-name]

DESCRIPTION

       The tune option allows you to alter some of the basic configuration values stored in the
       header area of a Round Robin Database (RRD).

       One application of the tune function is to relax the validation rules on an RRD. This
       allows to fill a new RRD with data available in larger intervals than what you would
       normally want to permit. Be very careful with tune operations for COMPUTE data sources.
       Setting the min, max, and  heartbeat for a COMPUTE data source without changing the data
       source type to a non-COMPUTE DST WILL corrupt the data source header in the RRD.

       A second application of the tune function is to set or alter parameters used by the
       specialized function RRAs for aberrant behavior detection.

       filename
               The name of the RRD you want to tune.

       --heartbeat|-h ds-name:heartbeat
               modify the heartbeat of a data source. By setting this to a high value the RRD
               will accept things like one value per day.

       --minimum|-i ds-name:min
               alter the minimum value acceptable as input from the data source.  Setting min to
               'U' will disable this limit.

       --maximum|-a ds-name:max
               alter the maximum value acceptable as input from the data source.  Setting max to
               'U' will disable this limit.

       --data-source-type|-d ds-name:DST
               alter the type DST of a data source.

       --data-source-rename|-r old-name:new-name
               rename a data source.

       --deltapos scale-value
               Alter the deviation scaling factor for the upper bound of the confidence band used
               internally to calculate violations for the FAILURES RRA. The default value is 2.
               Note that this parameter is not related to graphing confidence bounds which must
               be specified as a CDEF argument to generate a graph with confidence bounds. The
               graph scale factor need not to agree with the value used internally by the
               FAILURES RRA.

       --deltaneg scale-value
               Alter the deviation scaling factor for the lower bound of the confidence band used
               internally to calculate violations for the FAILURES RRA. The default value is 2.
               As with --deltapos, this argument is unrelated to the scale factor chosen when
               graphing confidence bounds.

       --failure-threshold failure-threshold
               Alter the number of confidence bound violations that constitute a failure for
               purposes of the FAILURES RRA. This must be an integer less than or equal to the
               window length of the FAILURES RRA. This restriction is not verified by the tune
               option, so one can reset failure-threshold and window-length simultaneously.
               Setting this option will reset the count of violations to 0.

       --window-length window-length
               Alter the number of time points in the temporal window for determining failures.
               This must be an integer greater than or equal to the window length of the FAILURES
               RRA and less than or equal to 28. Setting this option will reset the count of
               violations to 0.

       --alpha adaption-parameter
               Alter the intercept adaptation parameter for the Holt-Winters forecasting
               algorithm. This parameter must be between 0 and 1.

       --beta adaption-parameter
               Alter the slope adaptation parameter for the Holt-Winters forecasting algorithm.
               This parameter must be between 0 and 1.

       --gamma adaption-parameter
               Alter the seasonal coefficient adaptation parameter for the SEASONAL RRA. This
               parameter must be between 0 and 1.

       --gamma-deviation adaption-parameter
               Alter the seasonal deviation adaptation parameter for the DEVSEASONAL RRA. This
               parameter must be between 0 and 1.

       --smoothing-window fraction-of-season
               Alter the size of the smoothing window for the SEASONAL RRA. This must be between
               0 and 1.

       --smoothing-window-deviation fraction-of-season
               Alter the size of the smoothing window for the DEVSEASONAL RRA. This must be
               between 0 and 1.

       --aberrant-reset ds-name
               This option causes the aberrant behavior detection algorithm to reset for the
               specified data source; that is, forget all it is has learnt so far.  Specifically,
               for the HWPREDICT or MHWPREDICT RRA, it sets the intercept and slope coefficients
               to unknown. For the SEASONAL RRA, it sets all seasonal coefficients to unknown.
               For the DEVSEASONAL RRA, it sets all seasonal deviation coefficients to unknown.
               For the FAILURES RRA, it erases the violation history. Note that reset does not
               erase past predictions (the values of the HWPREDICT or MHWPREDICT RRA), predicted
               deviations (the values of the DEVPREDICT RRA), or failure history (the values of
               the FAILURES RRA).  This option will function even if not all the listed RRAs are
               present.

               Due to the implementation of this option, there is an indirect impact on other
               data sources in the RRD. A smoothing algorithm is applied to SEASONAL and
               DEVSEASONAL values on a periodic basis. During bootstrap initialization this
               smoothing is deferred. For efficiency, the implementation of smoothing is not data
               source specific. This means that utilizing reset for one data source will delay
               running the smoothing algorithm for all data sources in the file. This is unlikely
               to have serious consequences, unless the data being collected for the non-reset
               data sources is unusually volatile during the reinitialization period of the reset
               data source.

               Use of this tuning option is advised when the behavior of the data source time
               series changes in a drastic and permanent manner.

EXAMPLE 1

       "rrdtool tune data.rrd -h in:100000 -h out:100000 -h through:100000"

       Set the minimum required heartbeat for data sources 'in', 'out' and 'through' to 10'000
       seconds which is a little over one day in data.rrd.  This would allow to feed old data
       from MRTG-2.0 right into RRDtool without generating *UNKNOWN* entries.

EXAMPLE 2

       "rrdtool tune monitor.rrd --window-length 5 --failure-threshold 3"

       If the FAILURES RRA is implicitly created, the default window-length is 9 and the default
       failure-threshold is 7. This command now defines a failure as 3 or more violations in a
       temporal window of 5 time points.

AUTHOR

       Tobias Oetiker <tobi@oetiker.ch>