#!/bin/sh
# -*- sh -*-
#
# Plugin to monitor unusual activity/errors from ethernet driver/hardware.
#
# Parameters:
#
#   config   (required)
#   autoconf (optional - only used by munin-config)
#
# Environment variables (optional):
#
#   IGNORED_FIELDS: comma-separated list of fields (or field endings) to ignore
#   WARN: regex defining fields which trigger 'warning' on non-zero values
#   CRITICAL: regex defining fields which trigger 'critical' on non-zero values
#
# Author: Ted Dumitrescu (ted@mixpanel.com, webdev@cmme.org)
#
# Magic markers (optional - used by munin-config and some installation
# scripts):
#%# family=auto
#%# capabilities=autoconf


INTERFACE=${0##*ethtool_}
ETHTOOL="ethtool -S $INTERFACE"

if [ -z $IGNORED_FIELDS ]; then
  IGNORED_FIELDS='packets,bytes,broadcast,multicast,long_byte_count,offload_good,tcp_seg_good,smbus'
fi
if [ -z $WARN ]; then
  WARN='tx_.*restart.*'
fi
if [ -z $CRITICAL ]; then
  CRITICAL='(rx_no_buffer_count|rx_missed_errors|rx_queue_.+_drops)'
fi

TO_REMOVE=`echo $IGNORED_FIELDS | sed 's/,/\\\|/g'`
STRIP_OUTPUT="1d; s/^[ \t]*//; /\($TO_REMOVE\):/d"

if [ "$1" = "autoconf" ]; then
  $ETHTOOL 2>/dev/null >/dev/null
  if [ $? -ne 0 ]; then
    echo no
  else
    echo yes
  fi
  exit 0
fi

if [ "$1" = "config" ]; then
  echo "graph_title Ethtool $INTERFACE"
  echo 'graph_args -l 0 --base 1000'
  echo 'graph_category network'
  echo 'graph_period second'
  echo 'graph_info Unusual network hardware activity from ethtool'

  $ETHTOOL | sed "$STRIP_OUTPUT" | awk -F: -v WARN=$WARN -v CRITICAL=$CRITICAL '
    {
      printf("%s.label %s\n%s.type DERIVE\n%s.min 0\n", $1, $1, $1, $1);
      if ($1 ~ "^"WARN) {
        printf("%s.warning 0:0\n", $1);
      } else if ($1 ~ "^"CRITICAL) {
        printf("%s.critical 0:0\n", $1);
      }
    }'

  exit 0
fi

$ETHTOOL | sed "$STRIP_OUTPUT; s/:/.value/"