RRDUPDATE(1)                        rrdtool                       RRDUPDATE(1)



NAME
       rrdupdate - Store a new set of values into the RRD

SYNOPSIS
       rrdtool {update | updatev} filename [--template|-t ds-name[:ds-
       name]...]  N|timestamp:value[:value...]  at-timestamp@value[:value...]
       [timestamp:value[:value...] ...]

DESCRIPTION
       The update function feeds new data values into an RRD. The data is time
       aligned (interpolated) according to the properties of the RRD to which
       the data is written.

       updatev This alternate version of update takes the same arguments and
               performs the same function. The v stands for verbose, which
               describes the output returned. updatev returns a list of any
               and all consolidated data points (CDPs) written to disk as a
               result of the invocation of update. The values are indexed by
               timestamp (time_t), RRA (consolidation function and PDPs per
               CDP), and data source (name).  Note that depending on the argu-
               ments of the current and previous call to update, the list may
               have no entries or a large number of entries.

       filename
               The name of the RRD you want to update.

       --template|-t ds-name[:ds-name]...
               By default, the update function expects its data input in the
               order the data sources are defined in the RRD, excluding any
               COMPUTE data sources (i.e. if the third data source DST is COM-
               PUTE, the third input value will be mapped to the fourth data
               source in the RRD and so on). This is not very error resistant,
               as you might be sending the wrong data into an RRD.

               The template switch allows you to specify which data sources
               you are going to update and in which order. If the data sources
               specified in the template are not available in the RRD file,
               the update process will abort with an error message.

               While it appears possible with the template switch to update
               data sources asynchronously, RRDtool implicitly assigns non-
               COMPUTE data sources missing from the template the *UNKNOWN*
               value.

               Do not specify a value for a COMPUTE DST in the update func-
               tion. If this is done accidentally (and this can only be done
               using the template switch), RRDtool will ignore the value spec-
               ified for the COMPUTE DST.

       N|timestamp:value[:value...]
               The data used for updating the RRD was acquired at a certain
               time. This time can either be defined in seconds since
               1970-01-01 or by using the letter 'N', in which case the update
               time is set to be the current time. Negative time values are
               subtracted from the current time. An AT_STYLE TIME SPECIFICA-
               TION (see the rrdfetch documentation) may also be used by
               delimiting the end of the time specification with the '@' char-
               acter instead of a ':'. Getting the timing right to the second
               is especially important when you are working with data-sources
               of type COUNTER, DERIVE or ABSOLUTE.

               The remaining elements of the argument are DS updates. The
               order of this list is the same as the order the data sources
               were defined in the RRA. If there is no data for a certain
               data-source, the letter U (e.g., N:0.1:U:1) can be specified.

               The format of the value acquired from the data source is depen-
               dent on the data source type chosen. Normally it will be
               numeric, but the data acquisition modules may impose their very
               own parsing of this parameter as long as the colon (:) remains
               the data source value separator.

EXAMPLE
       "rrdtool update demo1.rrd N:3.44:3.15:U:23"

       Update the database file demo1.rrd with 3 known and one *UNKNOWN*
       value. Use the current time as the update time.

       "rrdtool update demo2.rrd 887457267:U 887457521:22 887457903:2.7"

       Update the database file demo2.rrd which expects data from a single
       data-source, three times. First with an *UNKNOWN* value then with two
       regular readings. The update interval seems to be around 300 seconds.

AUTHOR
       Tobias Oetiker <tobi@oetiker.ch>



1.2.30                            2009-01-19                      RRDUPDATE(1)
