#!/usr/bin/perl -w
# $Id: check_mem.pl 2 2002-02-28 06:42:51Z egalstad $
# Original script stolen from:
# check_mem.pl Copyright (C) 2000 Dan Larsson <dl@tyfon.net>
# hacked by
# Justin Ellison <justin@techadvise.com>
#
# This program is free software; you can redistribute it and/or
# modify it under the terms of the GNU General Public License
# as published by the Free Software Foundation; either version 2
# of the License, or (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty
# of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# you should have received a copy of the GNU General Public License
# along with this program (or with Nagios); if not, write to the
# Free Software Foundation, Inc., 59 Temple Place - Suite 330,
# Boston, MA 02111-1307, USA
# Tell Perl what we need to use
use strict;
use Getopt::Std;
#TODO - Convert to Nagios::Plugin
#TODO - Use an alarm
# Predefined exit codes for Nagios
use vars qw($opt_c $opt_f $opt_u $opt_w $opt_C $opt_v %exit_codes);
%exit_codes = ('UNKNOWN' ,-1,
'OK' , 0,
'WARNING' , 1,
'CRITICAL', 2,
);
# Get our variables, do our checking:
init();
# Get the numbers:
my ($free_memory_kb,$used_memory_kb,$caches_kb) = get_memory_info();
print "$free_memory_kb Free\n$used_memory_kb Used\n$caches_kb Cache\n" if ($opt_v);
if ($opt_C) { #Do we count caches as free?
$used_memory_kb -= $caches_kb;
$free_memory_kb += $caches_kb;
}
# Round to the nearest KB
$free_memory_kb = sprintf('%d',$free_memory_kb);
$used_memory_kb = sprintf('%d',$used_memory_kb);
$caches_kb = sprintf('%d',$caches_kb);
# Tell Nagios what we came up with
tell_nagios($used_memory_kb,$free_memory_kb,$caches_kb);
sub tell_nagios {
my ($used,$free,$caches) = @_;
# Calculate Total Memory
my $total = $free + $used;
print "$total Total\n" if ($opt_v);
my $perfdata = "|TOTAL=${total}KB;;;; USED=${used}KB;;;; FREE=${free}KB;;;; CACHES=${caches}KB;;;;";
if ($opt_f) {
my $percent = sprintf "%.1f", ($free / $total * 100);
if ($percent <= $opt_c) {
finish("CRITICAL - $percent% ($free kB) free!$perfdata",$exit_codes{'CRITICAL'});
}
elsif ($percent <= $opt_w) {
finish("WARNING - $percent% ($free kB) free!$perfdata",$exit_codes{'WARNING'});
}
else {
finish("OK - $percent% ($free kB) free.$perfdata",$exit_codes{'OK'});
}
}
elsif ($opt_u) {
my $percent = sprintf "%.1f", ($used / $total * 100);
if ($percent >= $opt_c) {
finish("CRITICAL - $percent% ($used kB) used!|$perfdata",$exit_codes{'CRITICAL'});
}
elsif ($percent >= $opt_w) {
finish("WARNING - $percent% ($used kB) used!|$perfdata",$exit_codes{'WARNING'});
}
else {
finish("OK - $percent% ($used kB) used.|$perfdata",$exit_codes{'OK'});
}
}
}
# Show usage
sub usage() {
print "\ncheck_mem.pl v1.0 - Nagios Plugin\n\n";
print "usage:\n";
print " check_mem.pl -<f|u> -w <warnlevel> -c <critlevel>\n\n";
print "options:\n";
print " -f Check FREE memory\n";
print " -u Check USED memory\n";
print " -C Count OS caches as FREE memory\n";
print " -w PERCENT Percent free/used when to warn\n";
print " -c PERCENT Percent free/used when critical\n";
print "\nCopyright (C) 2000 Dan Larsson <dl\@tyfon.net>\n";
print "check_mem.pl comes with absolutely NO WARRANTY either implied or explicit\n";
print "This program is licensed under the terms of the\n";
print "GNU General Public License (check source code for details)\n";
exit $exit_codes{'UNKNOWN'};
}
sub get_memory_info {
my $used_memory_kb = 0;
my $free_memory_kb = 0;
my $total_memory_kb = 0;
my $caches_kb = 0;
my $uname;
if ( -e '/usr/bin/uname') {
$uname = `/usr/bin/uname -a`;
}
elsif ( -e '/bin/uname') {
$uname = `/bin/uname -a`;
}
else {
die "Unable to find uname in /usr/bin or /bin!\n";
}
print "uname returns $uname" if ($opt_v);
if ( $uname =~ /Linux/ ) {
my @meminfo = `/bin/cat /proc/meminfo`;
foreach (@meminfo) {
chomp;
if (/^Mem(Total|Free):\s+(\d+) kB/) {
my $counter_name = $1;
if ($counter_name eq 'Free') {
$free_memory_kb = $2;
}
elsif ($counter_name eq 'Total') {
$total_memory_kb = $2;
}
}
elsif (/^(Buffers|Cached):\s+(\d+) kB/) {
$caches_kb += $2;
}
}
$used_memory_kb = $total_memory_kb - $free_memory_kb;
}
elsif ( $uname =~ /SunOS/ ) {
eval "use Sun::Solaris::Kstat";
if ($@) { #Kstat not available
if ($opt_C) {
print "You can't report on Solaris caches without Sun::Solaris::Kstat available!\n";
exit $exit_codes{UNKNOWN};
}
my @vmstat = `/usr/bin/vmstat 1 2`;
my $line;
foreach (@vmstat) {
chomp;
$line = $_;
}
$free_memory_kb = (split(/ /,$line))[5] / 1024;
my @prtconf = `/usr/sbin/prtconf`;
foreach (@prtconf) {
if (/^Memory size: (\d+) Megabytes/) {
$total_memory_kb = $1 * 1024;
}
}
$used_memory_kb = $total_memory_kb - $free_memory_kb;
}
else { # We have kstat
my $kstat = Sun::Solaris::Kstat->new();
my $phys_pages = ${kstat}->{unix}->{0}->{system_pages}->{physmem};
my $free_pages = ${kstat}->{unix}->{0}->{system_pages}->{freemem};
# We probably should account for UFS caching here, but it's unclear
# to me how to determine UFS's cache size. There's inode_cache,
# and maybe the physmem variable in the system_pages module??
# In the real world, it looks to be so small as not to really matter,
# so we don't grab it. If someone can give me code that does this,
# I'd be glad to put it in.
my $arc_size = (exists ${kstat}->{zfs} && ${kstat}->{zfs}->{0}->{arcstats}->{size}) ?
${kstat}->{zfs}->{0}->{arcstats}->{size} / 1024
: 0;
$caches_kb += $arc_size;
my $pagesize = `pagesize`;
$total_memory_kb = $phys_pages * $pagesize / 1024;
$free_memory_kb = $free_pages * $pagesize / 1024;
$used_memory_kb = $total_memory_kb - $free_memory_kb;
}
}
else {
if ($opt_C) {
print "You can't report on $uname caches!\n";
exit $exit_codes{UNKNOWN};
}
my $command_line = `vmstat | tail -1 | awk '{print \$4,\$5}'`;
chomp $command_line;
my @memlist = split(/ /, $command_line);
# Define the calculating scalars
$used_memory_kb = $memlist[0]/1024;
$free_memory_kb = $memlist[1]/1024;
$total_memory_kb = $used_memory_kb + $free_memory_kb;
}
return ($free_memory_kb,$used_memory_kb,$caches_kb);
}
sub init {
# Get the options
if ($#ARGV le 0) {
&usage;
}
else {
getopts('c:fuCvw:');
}
# Shortcircuit the switches
if (!$opt_w or $opt_w == 0 or !$opt_c or $opt_c == 0) {
print "*** You must define WARN and CRITICAL levels!\n";
&usage;
}
elsif (!$opt_f and !$opt_u) {
print "*** You must select to monitor either USED or FREE memory!\n";
&usage;
}
# Check if levels are sane
if ($opt_w <= $opt_c and $opt_f) {
print "*** WARN level must not be less than CRITICAL when checking FREE memory!\n";
&usage;
}
elsif ($opt_w >= $opt_c and $opt_u) {
print "*** WARN level must not be greater than CRITICAL when checking USED memory!\n";
&usage;
}
}
sub finish {
my ($msg,$state) = @_;
print "$msg\n";
exit $state;
}