RRDTUNE(1) rrdtool RRDTUNE(1)

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|-p scale-value] [--deltaneg|-n scale-
value] [--failure-threshold|-f failure-threshold]
[--window-length|-w window-length] [--alpha|-x adaption-parameter]
[--beta|-y adaption-parameter] [--gamma|-z adaption-parameter]
[--gamma-deviation|-v adaption-parameter]
[--smoothing-window|-s fraction-of-season]
[--smoothing-window-deviation|-S fraction-of-season]
[--aberrant-reset|-b ds-name] [--step|-t newstep]
[--daemon|-D address] [DEL:ds-name] [DS:ds-spec] [DELRRA:index]
[RRA:rra-spec] [RRA#index:[+-=]<number]>

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 you 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.

Still another application is to add or remove data sources (DS) or
add / remove or alter some aspects of round-robin archives (RRA).
These operations are not really done in-place, but rather generate a
new RRD file internally and move it over the original file. Data is
kept intact during these operations. For even more in-depth
modifications you may review the --source and --template options of
the create function which allow you to combine multiple RRD files
into a new one and which is even more clever in what data it is able
to keep or "regenerate".

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|-p 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|-n 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|-f 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|-w 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|-x adaption-parameter
Alter the intercept adaptation parameter for the Holt-Winters
forecasting algorithm. This parameter must be between 0 and
1.

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

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

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

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

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

--aberrant-reset|-b 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.

--step|-t newstep
Changes the step size of the RRD to newstep.

TODO: add proper documentation

--daemon|-D address
NOTE: Because the -d (small letter 'd') option was already
taken, this function (unlike most other) uses the capital
letter 'D' for the one-letter option to name the cache
daemon.

If given, RRDtool will try to connect to the caching daemon
rrdcached at address and will fail if the connection cannot
be established. If the connection is successfully established
the data for the filename will be flushed before performing
the copy/modify operation. Afterwards the filename will be
forgotten by the cache daemon, so that the next access using
the caching daemon will read the proper structure.

This sequence of operations is designed to achieve a
consistent overall result with respect to RRD internal file
consistency when using one of the DS or RRA changing
operations (that is: the resulting file should always be a
valid RRD file, regardless of concurrent updates through the
caching daemon). Regarding data consistency such guarantees
are not made: Without external synchronization concurrent
updates may be lost.

For a list of accepted formats, see the -l option in the
rrdcached manual.

DEL:ds-name
Every data source named with a DEL specification will be
removed. The resulting RRD will miss both the definition and
the data for that data source. Multiple DEL specifications
are permitted.

DS:ds-spec
For every such data source definition (for the exact syntax
see the create command), a new data source will be added to
the RRD. Multiple DS specifications are permitted.

DELRRA:index
Removes the RRA with index index. The index is zero-based,
that is the very first RRA has index 0.

RRA:rra-spec
For every such archive definition (for the exact syntax see
the create command), a new RRA will be added to the output
RRD. Multiple RRA specifications are permitted.

RRA#index:[+-=]<number>
Adds/removes or sets the given number of rows for the RRA
with index <index>. The index is zero-based, that is the very
first RRA has index 0.

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 100'000 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.

EXAMPLE 3
"rrdtool tune some.rrd DEL:a RRA#0:+10"

Delete the data source named a and extend the very first archive by
10 rows. This will in fact replace the input RRD with a new RRD
keeping all existing data. For most practical use cases this is
identical to a real in-place modification.

AUTHORS

Tobias Oetiker <tobi@oetiker.ch>, Peter Stamfest <peter@stamfest.at>

1.8.0 2022-03-14 RRDTUNE(1)