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>