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]...]  [--daemon address] [--] 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 arguments of the current and previous call to update, the list may have no entries or a large
	       number of entries.

	       Since updatev requires direct disk access, the --daemon option cannot be used with this command.

       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 COMPUTE, 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 function. If this is done accidentally (and this can only be done using the
	       template switch), RRDtool will ignore the value specified for the COMPUTE DST.

       --daemon address
	       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 values will be sent to the daemon instead of accessing the files
	       directly.

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

       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 SPECIFICATION (see the rrdfetch documentation) may also be used by delimiting the end of the time
	       specification with the '@' character 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.

	       When using negative time values, options and data have to be separated by two dashes (--), else the time value would be parsed as
	       an option.  See below for an example.

	       When using negative time values, options and data have to be separated by two dashes (--), else the time value would be parsed as
	       an option.  See below for an example.

	       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 dependent 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.

ENVIRONMENT VARIABLES

       The following environment variables may be used to change the behavior of "rrdtool update":

       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.

EXAMPLES

       o   "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.

       o   "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.

       o   "rrdtool update demo3.rrd -- -5:21 N:42"

	   Update the database file demo3.rrd two times, using five seconds in the past and the current time as the update times.

       o   "rrdtool update --cache /var/lib/rrd/demo3.rrd N:42"

	   Update the file "/var/lib/rrd/demo3.rrd" with a single data source, using the current time. If the caching daemon cannot be reached, do
	   not fall back to direct file access.

       o   "rrdtool update --daemon unix:/tmp/rrdd.sock demo4.rrd N:23"

	   Use the UNIX domain socket "/tmp/rrdd.sock" to contact the caching daemon. If the caching daemon is not available, update the file
	   "demo4.rrd" directly.  WARNING: Since a relative path is specified, the following disturbing effect may occur: If the daemon is
	   available, the file relative to the working directory of the daemon is used. If the daemon is not available, the file relative to the
	   current working directory of the invoking process is used.  This may update two different files depending on whether the daemon could
	   be reached or not. Don't do relative paths, kids!

AUTHORS

       Tobias Oetiker <tobi@oetiker.ch>, Florian Forster <octo at verplant.org>

1.4.3								    2009-06-02							      RRDUPDATE(1)