_R_R_D_T_U_N_E(1)                           rrdtool                          _R_R_D_T_U_N_E(1)

NNAAMMEE
     rrdtune - Modify some basic properties of a Round Robin Database

SSYYNNOOPPSSIISS
     rrrrddttooooll    ttuunnee    _f_i_l_e_n_a_m_e   [----hheeaarrttbbeeaatt|--hh _d_s_-_n_a_m_e:_h_e_a_r_t_b_e_a_t]   [----mmiinnii‐‐
     mmuumm|--ii _d_s_-_n_a_m_e:_m_i_n]                              [----mmaaxxiimmuumm|--aa _d_s_-_n_a_m_e:_m_a_x]
     [----ddaattaa--ssoouurrccee--ttyyppee|--dd _d_s_-_n_a_m_e:_D_S_T]                      [----ddaattaa--ssoouurrccee--rree‐‐
     nnaammee|--rr _o_l_d_-_n_a_m_e:_n_e_w_-_n_a_m_e]                      [----ddeellttaappooss|--pp _s_c_a_l_e_-_v_a_l_u_e]
     [----ddeellttaanneegg|--nn _s_c_a_l_e_-_v_a_l_u_e]      [----ffaaiilluurree--tthhrreesshhoolldd|--ff _f_a_i_l_u_r_e_-_t_h_r_e_s_h_o_l_d]
     [----wwiinnddooww--lleennggtthh|--ww _w_i_n_d_o_w_-_l_e_n_g_t_h]          [----aallpphhaa|--xx _a_d_a_p_t_i_o_n_-_p_a_r_a_m_e_t_e_r]
     [----bbeettaa|--yy _a_d_a_p_t_i_o_n_-_p_a_r_a_m_e_t_e_r] [----ggaammmmaa|--zz _a_d_a_p_t_i_o_n_-_p_a_r_a_m_e_t_e_r] [----ggaammmmaa--ddee‐‐
     vviiaattiioonn|--vv _a_d_a_p_t_i_o_n_-_p_a_r_a_m_e_t_e_r]   [----ssmmooootthhiinngg--wwiinnddooww|--ss _f_r_a_c_t_i_o_n_-_o_f_-_s_e_a_s_o_n]
     [----ssmmooootthhiinngg--wwiinnddooww--ddeevviiaattiioonn|--SS _f_r_a_c_t_i_o_n_-_o_f_-_s_e_a_s_o_n]        [----aabbeerrrraanntt--rree‐‐
     sseett|--bb _d_s_-_n_a_m_e]   [----sstteepp|--tt _n_e_w_s_t_e_p]  [----ddaaeemmoonn|--DD _a_d_d_r_e_s_s]  [DDEELL::_d_s_-_n_a_m_e]
     [DDSS::_d_s_-_s_p_e_c] [DDEELLRRRRAA::_i_n_d_e_x] [RRRRAA::_r_r_a_-_s_p_e_c] [RRRRAA##_i_n_d_e_x:[+-=]<number]>

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

     One application of the ttuunnee function is to relax the validation rules on an
     RRRRDD. This allows you to fill a new RRRRDD with data available in larger inter‐
     vals than what you would normally want to permit. Be very careful with tune
     operations  for COMPUTE data sources.  Setting the _m_i_n, _m_a_x, and  _h_e_a_r_t_b_e_a_t
     for a COMPUTE data source without  changing  the  data  source  type  to  a
     non-COMPUTE DDSSTT WILL corrupt the data source header in the RRRRDD.

     A  second  application  of  the ttuunnee function is to set or alter parameters
     used by the specialized function RRRRAAss 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 opera‐
     tions are not really done in-place, but rather generate a new RRD file  in‐
     ternally  and  move  it  over the original file. Data is kept intact during
     these operations.  For even more in-depth modifications you may review  the
     ----ssoouurrccee  and  ----tteemmppllaattee options of the ccrreeaattee 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".

     _f_i_l_e_n_a_m_eThe name of the RRRRDD you want to tune.

     ----hheeaarrttbbeeaatt|--hh _d_s_-_n_a_m_e:_h_e_a_r_t_b_e_a_t
             modify  the  _h_e_a_r_t_b_e_a_t  of a data source. By setting this to a high
             value the RRD will accept things like one value per day.

     ----mmiinniimmuumm|--ii _d_s_-_n_a_m_e:_m_i_n
             alter the minimum value acceptable as input from the  data  source.
             Setting _m_i_n to 'U' will disable this limit.

     ----mmaaxxiimmuumm|--aa _d_s_-_n_a_m_e:_m_a_x
             alter  the  maximum value acceptable as input from the data source.
             Setting _m_a_x to 'U' will disable this limit.

     ----ddaattaa--ssoouurrccee--ttyyppee|--dd _d_s_-_n_a_m_e:_D_S_T
             alter the type DDSSTT of a data source.

     ----ddaattaa--ssoouurrccee--rreennaammee|--rr _o_l_d_-_n_a_m_e:_n_e_w_-_n_a_m_e
             rename a data source.

     ----ddeellttaappooss|--pp _s_c_a_l_e_-_v_a_l_u_e
             Alter the deviation scaling factor for the upper bound of the  con‐
             fidence  band used internally to calculate violations for the FAIL‐
             URES RRRRAA. 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 RRRRAA.

     ----ddeellttaanneegg|--nn _s_c_a_l_e_-_v_a_l_u_e
             Alter  the deviation scaling factor for the lower bound of the con‐
             fidence band used internally to calculate violations for the  FAIL‐
             URES RRRRAA. The default value is 2. As with ----ddeellttaappooss, this argument
             is  unrelated  to  the scale factor chosen when graphing confidence
             bounds.

     ----ffaaiilluurree--tthhrreesshhoolldd|--ff _f_a_i_l_u_r_e_-_t_h_r_e_s_h_o_l_d
             Alter the number of confidence bound violations that  constitute  a
             failure  for  purposes of the FAILURES RRRRAA. This must be an integer
             less than or equal to the window length of the FAILURES  RRRRAA.  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.

     ----wwiinnddooww--lleennggtthh|--ww _w_i_n_d_o_w_-_l_e_n_g_t_h
             Alter  the  number of time points in the temporal window for deter‐
             mining failures. This must be an integer greater than or  equal  to
             the window length of the FAILURES RRRRAA and less than or equal to 28.
             Setting this option will reset the count of violations to 0.

     ----aallpphhaa|--xx _a_d_a_p_t_i_o_n_-_p_a_r_a_m_e_t_e_r
             Alter the intercept adaptation parameter for the Holt-Winters fore‐
             casting algorithm. This parameter must be between 0 and 1.

     ----bbeettaa|--yy _a_d_a_p_t_i_o_n_-_p_a_r_a_m_e_t_e_r
             Alter the slope adaptation parameter for the Holt-Winters forecast‐
             ing algorithm. This parameter must be between 0 and 1.

     ----ggaammmmaa|--zz _a_d_a_p_t_i_o_n_-_p_a_r_a_m_e_t_e_r
             Alter  the  seasonal  coefficient adaptation parameter for the SEA‐
             SONAL RRRRAA. This parameter must be between 0 and 1.

     ----ggaammmmaa--ddeevviiaattiioonn|--vv _a_d_a_p_t_i_o_n_-_p_a_r_a_m_e_t_e_r
             Alter the seasonal deviation adaptation parameter for  the  DEVSEA‐
             SONAL RRRRAA. This parameter must be between 0 and 1.

     ----ssmmooootthhiinngg--wwiinnddooww|--ss _f_r_a_c_t_i_o_n_-_o_f_-_s_e_a_s_o_n
             Alter  the  size of the smoothing window for the SEASONAL RRRRAA. This
             must be between 0 and 1.

     ----ssmmooootthhiinngg--wwiinnddooww--ddeevviiaattiioonn|--SS _f_r_a_c_t_i_o_n_-_o_f_-_s_e_a_s_o_n
             Alter the size of the smoothing window  for  the  DEVSEASONAL  RRRRAA.
             This must be between 0 and 1.

     ----aabbeerrrraanntt--rreesseett|--bb _d_s_-_n_a_m_e
             This option causes the aberrant behavior detection algorithm to re‐
             set  for  the  specified data source; that is, forget all it is has
             learnt so far.  Specifically, for the HWPREDICT or MHWPREDICT  RRRRAA,
             it  sets  the  intercept and slope coefficients to unknown. For the
             SEASONAL RRRRAA, it sets all seasonal coefficients to unknown. For the
             DEVSEASONAL RRRRAA, it sets all seasonal deviation coefficients to un‐
             known. For the FAILURES RRRRAA, it erases the violation history.  Note
             that  reset  does not erase past predictions (the values of the HW‐
             PREDICT or MHWPREDICT RRRRAA), predicted deviations (the values of the
             DEVPREDICT RRRRAA), or failure history (the  values  of  the  FAILURES
             RRRRAA).   This  option  will function even if not all the listed RRRRAAss
             are present.

             Due to the implementation of this option, there is an indirect  im‐
             pact on other data sources in the RRD. A smoothing algorithm is ap‐
             plied  to SEASONAL and DEVSEASONAL values on a periodic basis. Dur‐
             ing bootstrap initialization this smoothing is deferred. For  effi‐
             ciency,  the  implementation  of  smoothing is not data source spe‐
             cific. This means that utilizing reset for one data source will de‐
             lay 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.

     ----sstteepp|--tt _n_e_w_s_t_e_p
             Changes the step size of the RRD to newstep.

             TODO: add proper documentation

     ----ddaaeemmoonn|--DD _a_d_d_r_e_s_s
             NNOOTTEE:  Because  the --dd (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,  RRRRDDttooooll  will try to connect to the caching daemon rrd‐
             cached at _a_d_d_r_e_s_s and will fail if the connection cannot be  estab‐
             lished.  If the connection is successfully established the data for
             the _f_i_l_e_n_a_m_e will be flushed before performing the copy/modify  op‐
             eration.  Afterwards  the  _f_i_l_e_n_a_m_e  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 DDSS or RRRRAA changing operations (that is: the re‐
             sulting file should always be a valid RRD file, regardless of  con‐
             current  updates  through the caching daemon).  Regarding data con‐
             sistency such guarantees are not made:  Without  external  synchro‐
             nization concurrent updates may be lost.

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

     DDEELL::_d_s_-_n_a_m_e
             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.

     DDSS::_d_s_-_s_p_e_c
             For every such data source definition (for the exact syntax see the
             ccrreeaattee command), a new data source will be added to the RRD. Multi‐
             ple DS specifications are permitted.

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

     RRRRAA::_r_r_a_-_s_p_e_c
             For  every  such  archive  definition (for the exact syntax see the
             ccrreeaattee command), a new RRA will be added to the output RRD.  Multi‐
             ple RRA specifications are permitted.

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

EEXXAAMMPPLLEE 11
     "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.

EEXXAAMMPPLLEE 22
     "rrdtool tune monitor.rrd --window-length 5 --failure-threshold 3"

     If the FAILURES RRRRAA 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.

EEXXAAMMPPLLEE 33
     "rrdtool tune some.rrd DEL:a RRA#0:+10"

     Delete the data source named aa 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.

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

1.11.0                             2026-08-08                         _R_R_D_T_U_N_E(1)
