man Log::Log4perl::Appender::RRDs () - Log to a RRDtool Archive


Log::Log4perl::Appender::RRDs - Log to a RRDtool Archive


    use Log::Log4perl qw(get_logger);
    use RRDs;

    my $DB = "myrrddb.dat";

      $DB, "--step=1",

    print time(), "\n";

      log4perl.category = INFO, RRDapp
      log4perl.appender.RRDapp = Log::Log4perl::Appender::RRDs
      log4perl.appender.RRDapp.dbname = $DB
      log4perl.appender.RRDapp.layout = Log::Log4perl::Layout::PatternLayout
      log4perl.appender.RRDapp.layout.ConversionPattern = N:%m

    my $logger = get_logger();

    for(10, 15, 20, 25) {
        sleep 1;


CWLog::Log4perl::Appender::RRDs appenders facilitate writing data to RRDtool round-robin archives via Log4perl. For documentation on RRD and its Perl interface CWRRDs (which comes with the distribution), check out <>.

Messages sent to Log4perl's RRDs appender are expected to be numerical values (ints or floats), which then are used to run a CWrrdtool update command on an existing round-robin database. The name of this database needs to be set in the appender's CWdbname configuration parameter.

If there's more parameters you wish to pass to the CWupdate method, use the CWrrdupd_params configuration parameter:

    log4perl.appender.RRDapp.rrdupd_params = --template=in:out

To read out the round robin database later on, use CWrrdtool fetch or CWrrdtool graph for graphic displays.


Mike Schilli <>, 2004