Nagios Monitoring Server remaining memory

Linux system memory mechanism: In Linux there is such a thought, the memory is not white, so it as far as possible cache and buffer some data to facilitate the next use. But in fact, the memory is also available for immediate use. So free memory =free+buffers+cached

#!/bin/bash  usage= "' Basename $0 '  [-w|--warning]<percent free> [-c|-- Critical]<percent free> "  threshold_usage=" warning threshold must be  greater than critical:  ' basename $0 '  $* '   calc=/tmp/memcalc   Percent_free=/tmp/mempercent  critical= "  warning=" "  STATE_OK=0   State_warning=1  state_critical=2  state_unknown=3  # print usage   if [ $# -lt 4 ]; then      echo  " "      echo " wrong syntax:  ' basename $0 '  $* "       echo  ""       echo  "usage:  $USAGE"       echo  ""       exit 0  fi   # read input&Nbsp; while [ $# -gt 0 ]  do      case   "$"  in          -w|--warning)                shift               warning=$1               ;;           -c|--critical)                shift               critical=$1               ;;       esac      shift  done       # verify input  if [[  $warning -eq  $critical  | |   $warning  -lt  $critical  ]]; then      echo  ""       echo  "$THRESHOLD _usage"       echo  "      echo " usage:  $USAGE "      echo   ""       exit 0  fi  # total memory  available  total= ' free -m | head -2 |tail -1 |gawk  ' { print $2} '   # total memory used  used= ' Free -m | head  -3 |tail -1 |awk  ' {print $3} '   # calc total minus  used  free= ' free -m | head -3 |tail -1 |awk  ' {print  $4} '   # normal values   #echo   $total mb total  #echo   $used mb used   #echo   $free mb free  # make it  into % percent free =  ((FREE&NBSP;MEM&NBSP;/&NBSP;TOTAL&NBSP;MEM)  * 100)   echo  "5"  >  $calc  # decimal accuracy  echo  "K"  >>  $calc  # commit  echo  "+"  >>  $calc  #  multiply  echo  "$free"  >>  $calc  # division integer   echo  "$total"  >>  $calc  # division integer  echo  "/"   >>  $calc  # division sign  echo  "*"  >>  $calc  #  multiplication sign  echo  "P"  >>  $calc  # print   Percent= '/usr/bin/dc  $calc |/bin/sed  ' s/^\./0./' |/usr/bin/tr  '. "   " " |/usr/bin/gawk {' print $1 '} '  &nbsp: #percent1 = '/usr/bin/dc  $calc '    #echo   ' $percent 1   if [[  ' $percent " -le   $critical  ]];  then      echo " critical -  $free  MB  ($percent%)  free memory "       exit 2  fi  if [[  "$percent"  -le   $warning  ]];  then      echo  "warning -  $free  MB  ($percent%)   Free memory "      exit 1  fi  if [[ " $ Percent " -gt   $warning  ]]; then      echo " OK  -  $free  MB  ($percent%)  free memory "      exit  0  fi

This article is from the "Smurf Linux ops" blog, so be sure to keep this source http://jin771998569.blog.51cto.com/2147853/1636439

Nagios Monitoring Server remaining memory