check_openbsd_mem.sh

#!/bin/sh
#
# OpenBSD Memory Plugin for Nagios
# 
# The original verion of ths cscript was found here: 
#   https://exchange.nagios.org/directory/Plugins/Operating-Systems/BSD/OpenBSD/OpenBSD-Memory/details
#
# Updated the way the memory values are collected since top now outputs values in gigabytes
#
# Copyright 2008 - [email protected]
# Version: 0.2
# Date: 2008-12-31
#
# Description:
# This plugin checks the used/free/total
# memory of OpenBSD. You can set warning
# and critical integer/precentage(%) values 
# with -w and -c. With -p you can output
# performance data.
#
# Install:
# Install the nagios-plugins package, copy
# the script to /usr/local/libexec/nagios/
# and set the executable bit.
#
# Example usage:
# /usr/local/libexec/nagios/check_openbsd_mem.sh -w 15% -c 10% -p
# Will produce following output:
# OK - Free: 856M Used: 145M Total: 1001M | 856;145;1001;150;100
#
 
PROGNAME=$(echo $0 | awk -F\/ '{ print $NF }')
LIBEXEC="/usr/local/libexec/nagios"
. $LIBEXEC/utils.sh

print_usage()
{
  echo "Usage: $0 [-w <integer value>] [-c <integer value>] [-p]"
  echo "Usage: $0 -h"
  echo ""
  echo "Arguments:"
  echo "  -w <integer value>"
  echo "    Generate warning state if free memory under integer/percentage(%) value"
  echo "  -c <integer value>"
  echo "    Generate critical state if free memory under integer/percentage(%) value"
  echo "  -p"
  echo "    Output performance data"
  echo ""
}
print_help()
{
  echo "OpenBSD memory status plugin for Nagios"
  echo ""
  print_usage
}

while test -n "$1"; do
  case "$1" in
    -h)
      print_help
      exit $STATE_OK
      ;;
    -w)
      if [ $(echo $2 | grep "%$") ]; then
        percent_warn=$2 
      else
        int_warn=$2
      fi
      shift
      ;;
    -c)
      if [ $(echo $2 | grep "%$") ]; then
        percent_crit=$2 
      else
        int_crit=$2
      fi
      shift
      ;;
    -p)
      perf=1
      ;;
    *)
      echo "Unknown argument: $1"
      print_usage
      exit $STATE_UNKNOWN
      ;;
 esac
 shift
done

# get total memory
TOTAL_MEM=$(( $(sysctl -n hw.physmem) / 1024 / 1024 ))
# get free memory
FREE_MEM=$(vmstat | tail -1 | awk '{ print $4 }' | sed 's/M//g')
# calculate used memory
USED_MEM=$(($TOTAL_MEM - $FREE_MEM))

# checks -w and -c parameter and transform input
# percentage warning
if [ -n "$percent_warn" ]; then
  percent_warn=$(echo $percent_warn | sed 's/%//g')
  if [ $percent_warn -gt 100 ]; then
    echo "Error: Percentage of warning (-w) over 100%."
    exit $STATE_UNKNOWN
  else
    WARN=$(($TOTAL_MEM*$percent_warn/100))
  fi
fi
# percentage critical
if [ -n "$percent_crit" ]; then
  percent_crit=$(echo $percent_crit | sed 's/%//g')
  if [ $percent_crit -gt 100 ]; then
    echo "Error: Percentage of critical (-c) over 100%."
    exit $STATE_UNKNOWN
  else
    CRIT=$(($TOTAL_MEM*$percent_crit/100))
  fi
fi
# integer warning
if [ -n "$int_warn" ]; then
  WARN="$int_warn"
fi
# integer critical 
if [ -n "$int_crit" ]; then
  CRIT="$int_crit"
fi

# output with or without performance data
if [ "$perf" = 1 ]; then
  OUTPUT="Free: "$FREE_MEM"M Used: "$USED_MEM"M Total: "$TOTAL_MEM"M | $FREE_MEM;$USED_MEM;$TOTAL_MEM;$WARN;$CRIT"
else
  OUTPUT="Free: "$FREE_MEM"M Used: "$USED_MEM"M Total: "$TOTAL_MEM"M"
fi

# checks critical parameter if any specified
if [ -n "$CRIT" ]; then
  if [ $FREE_MEM -lt $CRIT ]; then
    echo -n "CIRTICAL - $OUTPUT"
    exit $STATE_CRITICAL
  fi
fi
# checks warning parameter if any specified
if [ -n "$WARN" ];then
  if [ $FREE_MEM -lt $WARN ]; then
    echo -n "WARNING - $OUTPUT"
    exit $STATE_WARNING
  fi
fi 

# output for STATE_OK
echo -n "OK - $OUTPUT"
exit $STATE_OK