check mem Plugin (NRPE)

#!/usr/bin/perl -w

# Heavily based on the script from:
# check_mem.pl Copyright (C) 2000 Dan Larsson <dl@tyfon.net>
# heavily modified by
# Justin Ellison <justin@techadvise.com>
#
# The MIT License (MIT)
# Copyright (c) 2011 justin@techadvise.com
# Permission is hereby granted, free of charge, to any person obtaining a copy of this
# software and associated documentation files (the "Software"), to deal in the Software
# without restriction, including without limitation the rights to use, copy, modify,
# merge, publish, distribute, sublicense, and/or sell copies of the Software, and to
# permit persons to whom the Software is furnished to do so, subject to the following conditions:
# The above copyright notice and this permission notice shall be included in all copies
# or substantial portions of the Software.
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
# INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR
# PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE
# FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT
# OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
# OTHER DEALINGS IN THE SOFTWARE.
# 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 $opt_v %exit_codes);
%exit_codes = ('UNKNOWN' , 3,
'OK' , 0,
'WARNING' , 1,
'CRITICAL', 2,
);
# Get our variables, do our checking:
init();
# Get the numbers:
my ($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 $perf_warn;
my $perf_crit;
if ( $opt_u ) {
$perf_warn = int(${total} * $opt_w / 100);
$perf_crit = int(${total} * $opt_c / 100);
}
my $perfdata = "|TOTAL=${total}KB;;;; USED=${used}KB;${perf_warn};${perf_crit};; FREE=${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 "MIT 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|SReclaimable):\s+(\d+) kB/) {
$caches_kb += $2;
}
}
$used_memory_kb = $total_memory_kb - $free_memory_kb;
}
elsif ( $uname =~ /HP-UX/ ) {
# HP-UX, thanks to Christoph Füler
my @meminfo = `/usr/bin/sudo /usr/local/bin/kmeminfo`;
foreach (@meminfo) {
chomp;
if (/^Physical memory\s\s+=\s+(\d+)\s+(\d+.\d)g/) {
$total_memory_kb = ($2 * 1024 * 1024);
}
elsif (/^Free memory\s\s+=\s+(\d+)\s+(\d+.\d)g/) {
$free_memory_kb = ($2 * 1024 * 1024);
}
}
$used_memory_kb = $total_memory_kb - $free_memory_kb;
}
elsif ( $uname =~ /FreeBSD/ ) {
# The FreeBSD case. 2013-03-19 www.claudiokuenzler.com
# free mem = Inactive*Page Size + Cache*Page Size + Free*Page Size
my $pagesize = `sysctl vm.stats.vm.v_page_size`;
$pagesize =~ s/[^0-9]//g;
my $mem_inactive = 0;
my $mem_cache = 0;
my $mem_free = 0;
my $mem_total = 0;
my $free_memory = 0;
my @meminfo = `/sbin/sysctl vm.stats.vm`;
foreach (@meminfo) {
chomp;
if (/^vm.stats.vm.v_inactive_count:\s+(\d+)/) {
$mem_inactive = ($1 * $pagesize);
}
elsif (/^vm.stats.vm.v_cache_count:\s+(\d+)/) {
$mem_cache = ($1 * $pagesize);
}
elsif (/^vm.stats.vm.v_free_count:\s+(\d+)/) {
$mem_free = ($1 * $pagesize);
}
elsif (/^vm.stats.vm.v_page_count:\s+(\d+)/) {
$mem_total = ($1 * $pagesize);
}
}
$free_memory = $mem_inactive + $mem_cache + $mem_free;
$free_memory_kb = ( $free_memory / 1024);
$total_memory_kb = ( $mem_total / 1024);
$used_memory_kb = $total_memory_kb - $free_memory_kb;
$caches_kb = ($mem_cache / 1024);
}
elsif ( $uname =~ /joyent/ ) {
# The SmartOS case. 2014-01-10 www.claudiokuenzler.com
# free mem = pagesfree * pagesize
my $pagesize = `pagesize`;
my $phys_pages = `kstat -p unix:0:system_pages:pagestotal | awk '{print \$NF}'`;
my $free_pages = `kstat -p unix:0:system_pages:pagesfree | awk '{print \$NF}'`;
my $arc_size = `kstat -p zfs:0:arcstats:size | awk '{print \$NF}'`;
my $arc_size_kb = $arc_size / 1024;
print "Pagesize is $pagesize" if ($opt_v);
print "Total pages is $phys_pages" if ($opt_v);
print "Free pages is $free_pages" if ($opt_v);
print "Arc size is $arc_size" if ($opt_v);
$caches_kb += $arc_size_kb;
$total_memory_kb = $phys_pages * $pagesize / 1024;
$free_memory_kb = $free_pages * $pagesize / 1024;
$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;
}
}
elsif ( $uname =~ /AIX/ ) {
my @meminfo = `/usr/bin/vmstat -v`;
foreach (@meminfo) {
chomp;
if (/^\s*([0-9.]+)\s+(.*)/) {
my $counter_name = $2;
if ($counter_name eq 'memory pages') {
$total_memory_kb = $1*4;
}
if ($counter_name eq 'free pages') {
$free_memory_kb = $1*4;
}
if ($counter_name eq 'file pages') {
$caches_kb = $1*4;
}
}
}
$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;
}