UCD-SNMP-MIB::memIndex.0 = INTEGER: 0
UCD-SNMP-MIB::memErrorName.0 = STRING: swap
UCD-SNMP-MIB::memTotalSwap.0 = INTEGER: 8385920 kB
UCD-SNMP-MIB::memAvailSwap.0 = INTEGER: 8385920 kB
UCD-SNMP-MIB::memTotalReal.0 = INTEGER: 8240104 kB
UCD-SNMP-MIB::memAvailReal.0 = INTEGER: 2576224 kB
UCD-SNMP-MIB::memTotalFree.0 = INTEGER: 10962144 kB
UCD-SNMP-MIB::memMinimumSwap.0 = INTEGER: 16000 kB
UCD-SNMP-MIB::memBuffer.0 = INTEGER: 326776 kB
UCD-SNMP-MIB::memCached.0 = INTEGER: 4740904 kB
[download]

#!C:\Dwimperl\perl\bin 

use strict;
use warnings;
use Net::SNMP;
use Nagios::Plugin;
use nagios::Plugin::Getopt;
use Math::Round;


my $np;

$np=Nagios::Plugin->new(
    usage         => "Usage: %s -H <host> -C <community> -w <warn> -c 
+<crit>",
    shortname    => "SNMP Memory",
    timeout        => 5,
    blurb         => "this plugin calculates the real used memory in l
+inux which includes the cache and buffers",
    extra         => "
    Examples: 
    
    check_snmp_mem.pl -H 127.0.0.1 -C public -w 90 -c 95
    
    
    "
);

# plugin arguments
$np->add_arg(
    spec        => "host|H=s",
    help        => "ip address or hostname of device",
    required    => 1,
);

$np->add_arg(
    spec        => "community|C=s",
    help        => "snmp community string",
    required    => 1,
);

$np->add_arg(
    spec        => "warning|w=i",
    help        => "usage in percent, when a WARNING is returned",
    required    => 1,
);

$np->add_arg(
    spec        => "critical|c=i",
    help        => " mem usage in percent, when a CRITICAL is returned
+",
    required    => 1,
);

$np->getopts;

# perform sanity checking on command line options
if ( (defined $np->opts->warning) && ($np->opts->warning < 0 || $np->o
+pts->warning > 100) )  {
    $np->nagios_die( " invalid number supplied for the -w option: ente
+r a value between 0 and 100 " );
}

if ( (defined $np->opts->warning) && ($np->opts->critical < 0 || $np->
+opts->critical > 100) )  {
    $np->nagios_die( " invalid number supplied for the -c option: ente
+r a value between 0 and 100 " );
}

if ( (defined $np->opts->warning) && ( $np->opts->warning > $np->opts-
+>critical) ) {
    $np->nagios_die( " invalid number supplied for the -w option: warn
+ing threshold should be smaller than critical threshold " );
}

my $memRealTotalOID = '.1.3.6.1.4.1.2021.4.5.0';
my $memRealFreeOID = '.1.3.6.1.4.1.2021.4.6.0';
my $memRealCachedOID = '.1.3.6.1.4.1.2021.4.15.0';
my $memRealBuffersOID = '.1.3.6.1.4.1.2021.4.14.0';

my ($session, $error) = Net::SNMP->session(
     -hostname  => $np->opts->host,
     -community => $np->opts->community,
   );

   if (!defined $session) {
      $np->nagios_exit (WARNING, $error)
      #printf "ERROR: %s.\n", $error;
   }

   my $memRealFree = $session->get_request(-varbindlist => [ $memRealF
+reeOID],);
   my $memRealTotal = $session->get_request(-varbindlist => [ $memReal
+TotalOID],);
   my $memRealCached = $session->get_request(-varbindlist => [ $memRea
+lCachedOID],);
   my $memRealBuffers = $session->get_request(-varbindlist => [ $memRe
+alBuffersOID],);

$session->close();

   my $buffers = $memRealBuffers->{$memRealBuffersOID}; 
   my $cache = $memRealCached->{$memRealCachedOID};
   my $total=  $memRealTotal->{$memRealTotalOID};
   my $free = $memRealFree->{$memRealFreeOID};
   
   my $memRealUsed = $total - $free;
   my $memRealUsedMB = round ($memRealUsed / 1024);
   my $totalMB = round($total / 1024);
  
   
  my $realTPercent = (($memRealUsed - $buffers - $cache)/ $total) * 10
+0;
  my $realPercent = sprintf "%.2f", $realTPercent;
  
  
 
$np->add_perfdata(
    label    =>    "Free",
    value    =>    $free,
    uom        =>    "KB"
);

$np->add_perfdata(
    label    =>    "Total",
    value    =>    $total,
    uom        =>    "KB"
);

$np->add_perfdata(
    label    =>    "Cached",
    value    =>    $cache,
    uom        =>    "KB"
);

$np->add_perfdata(
    label    =>    "Buffered",
    value    =>    $buffers,
    uom        =>    "KB"
);


 #####################################################################
+#########
# check the result against the defined warning and critical thresholds
+,
# output the result and exit
$np->nagios_exit( 
     return_code => $np->check_threshold($realPercent), 
     message => " used: $realPercent% with $memRealUsedMB MB of $total
+MB MB free" 
);
[download]

Surely I don't understand the question - it looks like you are asking how to eliminate e.g. the $cache variable, but that seems too simple given your apparently higher skill level.!

One world, one people

Hello


That is my question for now...I have used mainly the examples of the Nagios::Plugin and Net::SNMP to build the script..

The object returned by Net::SNMP get_request is a hash how can I make arithmetic operation on the values returned by those. the only workaround I found was to extract the value in a temporary variable..

I am in my first baby steps in Perl.