#!@@GOODSH@@
# -*- sh -*-
#
# Plugin to monitor the load average on a system.
#
# Usage: Link or copy into /etc/munin/node.d/
#
# Magic markers (optional - only used by munin-config and some
# installation scripts):
#
#%# family=auto
#%# capabilities=autoconf



# If run with the "autoconf"-parameter, give our opinion on whether we
# should be run on this system or not. This is optional, and only used
# by munin-config. In the case of this plugin, we should most probably
# always be included.

if [ "$1" = "autoconf" ]; then
    if [ -x /sbin/sysctl ]; then
        /sbin/sysctl vm.loadavg > /dev/null
        if [ $? = "0" ]; then
                echo yes
                exit 0
        else
                    echo no
                    exit 0
            fi
    else
        echo no
        exit 0
    fi
fi

# If run with the "config"-parameter, give out information on how the
# graphs should look.

if [ "$1" = "config" ]; then
        # The host name this plugin is for. (Can be overridden to have
        # one machine answer for several)

        # The title of the graph
        echo 'graph_title Load average'
        # Arguments to "rrdtool graph". In this case, tell it that the
        # lower limit of the graph is '0', and that 1k=1000 (not 1024)
        echo 'graph_args --base 1000 -l 0'
        # The Y-axis label
        echo 'graph_vlabel load'
        # We want Cur/Min/Avg/Max unscaled (i.e. 0.42 load instead of
        # 420 milliload)
        echo 'graph_noscale true'
        # The category of the plugin. Defaults to "other".
        echo 'graph_category system'
        # The fields. "label" is used in the legend. "label" is the only
        # required subfield.
        echo 'load.label load'
        # These two are optional. They are only used if you have
        # configured your munin to tell a Nagios-server about any
        # problems
        echo 'load.warning 10'
        echo 'load.critical 120'
        # This one is purely to add an explanation to the web page. The first
        # one is for the graph itself, while the second one is for the field
        # "load".
        echo 'graph_info The load average of the machine describes how many processes are in the run-queue (scheduled to run "immediately").'
        echo 'load.info Average load for the five minutes.'

        # Last, if run with the "config"-parameter, quit here (don't
        # display any data)
        exit 0
fi

# If not run with any parameters at all (or only unknown ones), do the
# real work - i.e. display the data. Almost always this will be
# "value" subfield for every data field.

echo -n "load.value "
/sbin/sysctl vm.loadavg | cut -f3 -d' '

# How could this plugin have been written in its simplest form?
# Something like this:
#
# ---------------------
# #!/bin/sh

#
# if [ "$1" = "config" ]; then

#       echo "graph_title Load average"
#	echo 'graph_args --base 1000 -l 0'
#	echo 'graph_vlabel load'
#       echo "load.label load"
#       exit 0
# fi
# echo -n "load.value "
# cut -f1 -d' ' < /proc/loadavg
# ---------------------
#
# Except for the Nagios-warnings (which most people don't have any need
# for) and things used by installation scripts and munin-config (which
# you don't need if you don't plan on submitting your plugin to the
# pacakge), the two versions will work identically.