check_iftraffic

#!/usr/bin/perl -w

#

# check_iftraffic.pl - Nagios(r) network traffic monitor plugin

# Copyright (C) 2004 Gerd Mueller / Netways GmbH

# $Id: check_iftraffic.pl 1119 2006-02-09 10:30:09Z gmueller $

#

# mw = Markus Werner mw+nagios@wobcom.de

# Remarks (mw):

#

# I adopted as much as possible the programming style of the origin code.

#

# There should be a function to exit this programm,

# instead of calling print and exit statements all over the place.

#

#

# minor changes by mw

# The snmp if_counters on net devices can have overflows.

# I wrote this code to address this situation.

# It has no automatic detection and which point the overflow

# occurs but it will generate a warning state and you

# can set the max value by calling this script with an additional

# arg.

#

# minor cosmetic changes by mw

# Sorry but I couldn't sustain to clean up some things.

#

# based on check_traffic from Adrian Wieczorek, <ads (at) irc.pila.pl>

#

# Send us bug reports, questions and comments about this plugin.

# Latest version of this software: http://www.nagiosexchange.org

#

#

# 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; if not, write to the Free Software

# Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307

use strict;

use Net::SNMP;

use Getopt::Long;

&Getopt::Long::config('bundling');

use Data::Dumper;

my $host_address;

my $iface_number;

my $iface_descr;

my $iface_speed;

my $opt_h;

my $units;

my $session;

my $error;

my $port = 161;

my $snmp_version = 1;

my @snmpoids;

# SNMP OIDs for Traffic

my $snmpIfInOctets = '1.3.6.1.2.1.2.2.1.10';

my $snmpIfOutOctets = '1.3.6.1.2.1.2.2.1.16';

my $snmpIfDescr = '1.3.6.1.2.1.2.2.1.2';

my $response;

# Path to tmp files

my $TRAFFIC_FILE = "/tmp/traffic";

my %STATUS_CODE =

( 'UNKNOWN' => '-1', 'OK' => '0', 'WARNING' => '1', 'CRITICAL' => '2' );

#default values;

my ( $in_bytes, $out_bytes ) = 0;

my $warn_usage = 85;

my $crit_usage = 98;

my $COMMUNITY = "public";

#added 20050614 by mw

my $max_value;

my $max_bytes;

#cosmetic changes 20050614 by mw, see old versions for detail

my $status = GetOptions(

"h|help" => \$opt_h,

"C|community=s" => \$COMMUNITY,

"w|warning=s" => \$warn_usage,

"c|critical=s" => \$crit_usage,

"b|bandwidth=i" => \$iface_speed,

"p|port=i" => \$port,

"u|units=s" => \$units,

"i|interface=s" => \$iface_descr,

"H|hostname=s" => \$host_address,

#added 20050614 by mw

"M|max=i" => \$max_value

);

if ( $status == 0 ) {

print_help();

exit $STATUS_CODE{'OK'};

}

if ( ( !$host_address ) or ( !$iface_descr ) or ( !$iface_speed ) ) {

print_usage();

}

#change 20050414 by mw

$iface_speed = bits2bytes( $iface_speed, $units ) / 1024;

if ( !$max_value ) {

#if no -M Parameter was set, set it to 32Bit Overflow

$max_bytes = 419304; # the value is (2^32/1024)

}

else {

$max_bytes = unit2bytes( $max_value, $units );

}

if ( $snmp_version =~ /[12]/ ) {

( $session, $error ) = Net::SNMP->session(

-hostname => $host_address,

-community => $COMMUNITY,

-port => $port,

-version => $snmp_version

);

if ( !defined($session) ) {

print("UNKNOWN: $error");

exit $STATUS_CODE{'UNKNOWN'};

}

}

elsif ( $snmp_version =~ /3/ ) {

my $state = 'UNKNOWN';

print("$state: No support for SNMP v3 yet\n");

exit $STATUS_CODE{$state};

}

else {

my $state = 'UNKNOWN';

print("$state: No support for SNMP v$snmp_version yet\n");

exit $STATUS_CODE{$state};

}

$iface_number = fetch_ifdescr( $session, $iface_descr );

push( @snmpoids, $snmpIfInOctets . "." . $iface_number );

push( @snmpoids, $snmpIfOutOctets . "." . $iface_number );

if ( !defined( $response = $session->get_request(@snmpoids) ) ) {

my $answer = $session->error;

$session->close;

print("WARNING: SNMP error: $answer\n");

exit $STATUS_CODE{'WARNING'};

}

$in_bytes = $response->{ $snmpIfInOctets . "." . $iface_number } / 1024;

$out_bytes = $response->{ $snmpIfOutOctets . "." . $iface_number } / 1024;

$session->close;

my $row;

my $last_check_time = time - 1;

my $last_in_bytes = $in_bytes;

my $last_out_bytes = $out_bytes;

if (

open( FILE,

"<" . $TRAFFIC_FILE . "_if" . $iface_number . "_" . $host_address

)

)

{

while ( $row = <FILE> ) {

#cosmetic change 20050416 by mw

#Couldn't sustain;-)

chomp($row);

( $last_check_time, $last_in_bytes, $last_out_bytes ) =

split( ":", $row );

}

close(FILE);

}

my $update_time = time;

open( FILE, ">" . $TRAFFIC_FILE . "_if" . $iface_number . "_" . $host_address )

or die "Can't open $TRAFFIC_FILE for writing: $!";

printf FILE ( "%s:%.0ld:%.0ld\n", $update_time, $in_bytes, $out_bytes );

close(FILE);

my $db_file;

#added 20050614 by mw

#Check for and correct counter overflow (if possible).

#See function counter_overflow.

$in_bytes = counter_overflow( $in_bytes, $last_in_bytes, $max_bytes );

$out_bytes = counter_overflow( $out_bytes, $last_out_bytes, $max_bytes );

my $in_traffic = sprintf( "%.2lf",

( $in_bytes - $last_in_bytes ) / ( time - $last_check_time ) );

my $out_traffic = sprintf( "%.2lf",

( $out_bytes - $last_out_bytes ) / ( time - $last_check_time ) );

my $in_traffic_absolut = sprintf( "%.0d", $last_in_bytes );

my $out_traffic_absolut = sprintf( "%.0d", $last_out_bytes );

my $in_usage = sprintf( "%.1f", ( 1.0 * $in_traffic * 100 ) / $iface_speed );

my $out_usage = sprintf( "%.1f", ( 1.0 * $out_traffic * 100 ) / $iface_speed );

my $in_prefix = "k";

my $out_prefix = "k";

if ( $in_traffic > 1024 ) {

$in_traffic = sprintf( "%.2f", $in_traffic / 1024 );

$in_prefix = "M";

}

if ( $out_traffic > 1024 ) {

$out_traffic = sprintf( "%.2f", $out_traffic / 1024 );

$out_prefix = "M";

}

$in_bytes = sprintf( "%.2f", $in_bytes / 1024 );

$out_bytes = sprintf( "%.2f", $out_bytes / 1024 );

my $exit_status = "OK";

my $output = "Total RX Bytes: $in_bytes MB, Total TX Bytes: $out_bytes MB<br>";

$output .=

"Average Traffic: $in_traffic "

. $in_prefix . "B/s ("

. $in_usage

. "%) in, $out_traffic "

. $out_prefix . "B/s ("

. $out_usage

. "%) out";

if ( ( $in_usage > $crit_usage ) or ( $out_usage > $crit_usage ) ) {

$exit_status = "CRITICAL";

}

if ( ( $in_usage > $warn_usage )

or ( $out_usage > $warn_usage ) && $exit_status eq "OK" )

{

$exit_status = "WARNING";

}

$output .= "<br>$exit_status bandwidth utilization.\n"

if ( $exit_status ne "OK" );

$output .=

"| inUsage=$in_usage,$warn_usage,$crit_usage outUsage=$out_usage,$warn_usage,$crit_usage "

. "inAbsolut=$in_traffic_absolut outAbsolut=$out_traffic_absolut\n";

print $output;

exit( $STATUS_CODE{$exit_status} );

sub fetch_ifdescr {

my $state;

my $response;

my $snmpkey;

my $answer;

my $key;

my ( $session, $ifdescr ) = @_;

if ( !defined( $response = $session->get_table($snmpIfDescr) ) ) {

$answer = $session->error;

$session->close;

$state = 'CRITICAL';

$session->close;

exit $STATUS_CODE{$state};

}

foreach $key ( keys %{$response} ) {

if ( $response->{$key} =~ /^$ifdescr$/ ) {

$key =~ /.*\.(\d+)$/;

$snmpkey = $1;

# print "$ifdescr = $key / $snmpkey \n"; #debug

}

}

unless ( defined $snmpkey ) {

$session->close;

$state = 'CRITICAL';

printf "$state: Could not match $ifdescr \n";

exit $STATUS_CODE{$state};

}

return $snmpkey;

}

#added 20050416 by mw

#Converts an input value to value in bits

sub bits2bytes {

return unit2bytes(@_) / 8;

}

#added 20050416 by mw

#Converts an input value to value in bytes

sub unit2bytes {

my ( $value, $unit ) = @_;

if ( $unit eq "g" ) {

return $value * 1024 * 1024 * 1024;

}

elsif ( $unit eq "m" ) {

return $value * 1024 * 1024;

}

elsif ( $unit eq "k" ) {

return $value * 1024;

}

else {

print "You have to supplie a supported unit\n";

exit $STATUS_CODE{'UNKNOWN'};

}

}

#added 20050414 by mw

#This function detects if an overflow occurs. If so, it returns

#a computed value for $bytes.

#If there is no counter overflow it simply returns the origin value of $bytes.

sub counter_overflow {

my ( $bytes, $last_bytes, $max_bytes ) = @_;

$bytes += $max_bytes if ( $bytes < $last_bytes );

$bytes = 0 if ( $bytes < $last_bytes );

return $bytes;

}

#cosmetic changes 20050614 by mw

#Couldn't sustaine "HERE";-), either.

sub print_usage {

print <<EOU;

Usage: check_iftraffic.pl -H host -i if_descr -b if_max_speed [ -w warn ] [ -c crit ]

Options:

-H --host STRING or IPADDRESS

Check interface on the indicated host.

-C --community STRING

SNMP Community.

-i --interface STRING

Interface Name

-b --bandwidth INTEGER

Interface maximum speed in kilo/mega/giga/bits per second.

-u --units STRING

gigabits/s,m=megabits/s,k=kilobits/s,b=bits/s.

-w --warning INTEGER

% of bandwidth usage necessary to result in warning status (default: 85%)

-c --critical INTEGER

% of bandwidth usage necessary to result in critical status (default: 98%)

-M --max INTEGER

Max Counter Value of net devices in kilo/mega/giga/bytes.

EOU

exit( $STATUS_CODE{"UNKNOWN"} );

}