RRDINFO(1)                           rrdtool                          RRDINFO(1)

NAME
     rrdinfo - extract header information from an RRD

SYNOPSIS
     rrdtool info filename [--daemon|-d address [--noflush|-F]]

DESCRIPTION
     The  info  function  prints the header information from an RRD in a parsing
     friendly format.

     Check rrdcreate if you are uncertain about the meaning  of  the  individual
     keys.

     filenameThe name of the RRD you want to examine.

     --daemon|-d address
             Address of the rrdcached daemon. If specified, a "flush" command is
             sent  to  the server before reading the RRD files. This allows rrd‐
             tool to return fresh data even if the daemon is configured to cache
             values for a long time.  For a list of accepted formats, see the -l
             option in the rrdcached manual.

              rrdtool info --daemon unix:/var/run/rrdcached.sock /var/lib/rrd/foo.rrd

     --noflush|-F
             Omit the "flush" command usually sent to the daemon  prior  to  re‐
             trieving  the data.  If all you are interested in is the RRD struc‐
             ture, and not the last update time or  current  values,  then  this
             will improve efficiency.

EXAMPLE
     This is the output generated by running info on a simple RRD which contains
     two  data  sources  and one RRA. Note that the number after the last_update
     keyword is in seconds since 1970. The string NaN stands for *UNKNOWN* data.
     In the example it means that this RRD has neither minimum nor maximum  val‐
     ues defined for either of its data sources.

      filename = "random.rrd"
      rrd_version = "0001"
      step = 300
      last_update = 955892996
      header_size = 2872
      ds[a].type = "GAUGE"
      ds[a].minimal_heartbeat = 600
      ds[a].min = NaN
      ds[a].max = NaN
      ds[a].last_ds = "UNKN"
      ds[a].value = 2.1824421548e+04
      ds[a].unknown_sec = 0
      ds[b].type = "GAUGE"
      ds[b].minimal_heartbeat = 600
      ds[b].min = NaN
      ds[b].max = NaN
      ds[b].last_ds = "UNKN"
      ds[b].value = 3.9620838224e+03
      ds[b].unknown_sec = 0
      rra[0].cf = "AVERAGE"
      rra[0].pdp_per_row = 1
      rra[0].cdp_prep[0].value = nan
      rra[0].cdp_prep[0].unknown_datapoints = 0
      rra[0].cdp_prep[1].value = nan
      rra[0].cdp_prep[1].unknown_datapoints = 0

ENVIRONMENT VARIABLES
     The  following  environment variables may be used to change the behavior of
     "rrdtool info":

     RRDCACHED_ADDRESS
         If this environment variable is set it will have  the  same  effect  as
         specifying  the  "--daemon"  option  on  the  command line. If both are
         present, the command line argument takes precedence.

AUTHOR
     Tobias Oetiker <tobi@oetiker.ch>

1.10.0                             2026-05-25                         RRDINFO(1)
