#!/bin/sh
#
# Plugin to monitor ARP entries per interface
#
# Parameters understood:
#
#       config   (required)
#       autoconf (optional)
#
#  Made by Sven Hartge (sven AT svenhartge DOT de)
#
#


#%# family=contrib
#%# capabilities=autoconf suggest

INTERFACE=`basename $0 | sed 's/^arp_//g' | tr '_' '.'`

if [ "$1" = "autoconf" ]; then
    # Search for arp
    which arp >/dev/null 2>/dev/null || (echo "no (can't find arp binary)" && exit 1)

    # ...or success
    echo yes
    exit 0
fi

if [ "$1" = "suggest" ]; then
  if [ -r /proc/net/dev ]; then
    egrep '^ *(eth|wlan|ath|ra)[0-9]+(\.[0-9]+)?:' /proc/net/dev | cut -f1 -d: | sed 's/ //g' | tr '.' '_'
    exit 0
  else
    exit 1
  fi
fi



if [ "$1" = "config" ]; then
        echo "graph_title ARP entries for $INTERFACE"
        echo 'graph_args --base 1000 -l 0'
        echo 'graph_vlabel Entries'
        echo 'graph_category network'
	echo 'graph_scale no'
        echo "graph_info This graph shows the number of ARP entries registered by the system for interface $INTERFACE."
	echo 'entries.label ARP entries'
	echo 'entries.draw LINE2'
	echo 'entries.type GAUGE'
	echo 'entries.info Number of ARP entries'
	exit 0
fi

arp -an -i $INTERFACE | awk 'BEGIN { regex="<incomplete>";} { if (!match($4,regex)) { a[$4] }} END{for(i in a){n++};print "entries.value " n}'