contrib/check_mem.pl

   1 #!/usr/bin/perl -w
   2 # $Id$
   3
   4 # check_mem.pl Copyright (C) 2000 Dan Larsson <dl@tyfon.net>
   5 #
   6 # This program is free software; you can redistribute it and/or
   7 # modify it under the terms of the GNU General Public License
   8 # as published by the Free Software Foundation; either version 2
   9 # of the License, or (at your option) any later version.
  10 #
  11 # This program is distributed in the hope that it will be useful,
  12 # but WITHOUT ANY WARRANTY; without even the implied warranty
  13 # of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 # GNU General Public License for more details.
  15 #
  16 # you should have received a copy of the GNU General Public License
  17 # along with this program (or with Nagios);  if not, write to the
  18 # Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  19 # Boston, MA 02111-1307, USA
  20
  21 # Tell Perl what we need to use
  22 use strict;
  23 use Getopt::Std;
  24
  25 use vars qw($opt_c $opt_f $opt_u $opt_w
  26             $free_memory $used_memory $total_memory
  27             $crit_level $warn_level
  28             %exit_codes @memlist
  29             $percent $fmt_pct
  30             $verb_err $command_line);
  31
  32 # Predefined exit codes for Nagios
  33 %exit_codes   = ('UNKNOWN' ,-1,
  34                  'OK'      , 0,
  35                  'WARNING' , 1,
  36                  'CRITICAL', 2,);
  37
  38 # Turn this to 1 to see reason for parameter errors (if any)
  39 $verb_err     = 0;
  40
  41 # This the unix command string that brings Perl the data
  42 $command_line = `vmstat | tail -1 | awk '{print \$4,\$5}'`;
  43
  44 chomp $command_line;
  45 @memlist      = split(/ /, $command_line);
  46
  47 # Define the calculating scalars
  48 $used_memory  = $memlist[0];
  49 $free_memory  = $memlist[1];
  50 $total_memory = $used_memory + $free_memory;
  51
  52 # Get the options
  53 if ($#ARGV le 0)
  54 {
  55   &usage;
  56 }
  57 else
  58 {
  59   getopts('c:fuw:');
  60 }
  61
  62 # Shortcircuit the switches
  63 if (!$opt_w or $opt_w == 0 or !$opt_c or $opt_c == 0)
  64 {
  65   print "*** You must define WARN and CRITICAL levels!" if ($verb_err);
  66   &usage;
  67 }
  68 elsif (!$opt_f and !$opt_u)
  69 {
  70   print "*** You must select to monitor either USED or FREE memory!" if ($verb_err);
  71   &usage;
  72 }
  73
  74 # Check if levels are sane
  75 if ($opt_w <= $opt_c and $opt_f)
  76 {
  77   print "*** WARN level must not be less than CRITICAL when checking FREE memory!" if ($verb_err);
  78   &usage;
  79 }
  80 elsif ($opt_w >= $opt_c and $opt_u)
  81 {
  82   print "*** WARN level must not be greater than CRITICAL when checking USED memory!" if ($verb_err);
  83   &usage;
  84 }
  85
  86 $warn_level   = $opt_w;
  87 $crit_level   = $opt_c;
  88
  89 if ($opt_f)
  90 {
  91   $percent    = $free_memory / $total_memory * 100;
  92   $fmt_pct    = sprintf "%.1f", $percent;
  93   if ($percent <= $crit_level)
  94   {
  95     print "Memory CRITICAL - $fmt_pct% ($free_memory kB) free\n";
  96     exit $exit_codes{'CRITICAL'};
  97   }
  98   elsif ($percent <= $warn_level)
  99   {
 100     print "Memory WARNING - $fmt_pct% ($free_memory kB) free\n";
 101     exit $exit_codes{'WARNING'};
 102   }
 103   else
 104   {
 105     print "Memory OK - $fmt_pct% ($free_memory kB) free\n";
 106     exit $exit_codes{'OK'};
 107   }
 108 }
 109 elsif ($opt_u)
 110 {
 111   $percent    = $used_memory / $total_memory * 100;
 112   $fmt_pct    = sprintf "%.1f", $percent;
 113   if ($percent >= $crit_level)
 114   {
 115     print "Memory CRITICAL - $fmt_pct% ($used_memory kB) used\n";
 116     exit $exit_codes{'CRITICAL'};
 117   }
 118   elsif ($percent >= $warn_level)
 119   {
 120     print "Memory WARNING - $fmt_pct% ($used_memory kB) used\n";
 121     exit $exit_codes{'WARNING'};
 122   }
 123   else
 124   {
 125     print "Memory OK - $fmt_pct% ($used_memory kB) used\n";
 126     exit $exit_codes{'OK'};
 127   }
 128 }
 129
 130 # Show usage
 131 sub usage()
 132 {
 133   print "\ncheck_mem.pl v1.0 - Nagios Plugin\n\n";
 134   print "usage:\n";
 135   print " check_mem.pl -<f|u> -w <warnlevel> -c <critlevel>\n\n";
 136   print "options:\n";
 137   print " -f           Check FREE memory\n";
 138   print " -u           Check USED memory\n";
 139   print " -w PERCENT   Percent free/used when to warn\n";
 140   print " -c PERCENT   Percent free/used when critical\n";
 141   print "\nCopyright (C) 2000 Dan Larsson <dl\@tyfon.net>\n";
 142   print "check_mem.pl comes with absolutely NO WARRANTY either implied or explicit\n";
 143   print "This program is licensed under the terms of the\n";
 144   print "GNU General Public License (check source code for details)\n";
 145   exit $exit_codes{'UNKNOWN'};
 146 }