snmp_traffic.pl

#!/usr/bin/perl -w

use strict;
use Net::SNMP;

my $session = Net::SNMP->session (-hostname => "serenity", -community => "public");

die("No session!\n") if (!defined($session));

my $ifDescr = "1.3.6.1.2.1.2.2.1.2.1";
my $ifInOctets = "1.3.6.1.2.1.2.2.1.10.1";
my $ifOutOctets = "1.3.6.1.2.1.2.2.1.16.1";

sub getTraffic {
	my $result = $session->get_request(-varbindlist => [$ifDescr, $ifInOctets, $ifOutOctets]);
	if (!defined($result)) { print "error: ", $session->error() };
	return $result;
}

sub sum {
	my $ret;
	$ret += $_ for @_;
	return $ret;
}

print "Querying the router.\n";

my @results;
my $checks = 6;
my $time = 30;

for (1 .. ($checks - 1)) {
	push(@results, [getTraffic(), time()]);
	sleep($time / ($checks - 1));
}

push(@results, [getTraffic(), time()]);

my @inRates;
my @outRates;
my $inDelta;
my $outDelta; 

for my $i (1 .. $#results) {
    my ($prev, $item) = map {$_=>[0]} @results[$i-1, $i];
    my $time = $results[$i]->[1] - $results[$i - 1]->[1];
	$inDelta = $item->{$ifInOctets} - $prev->{$ifInOctets};
	$outDelta = $item->{$ifOutOctets} - $prev->{$ifOutOctets};
	$inDelta *= 8;
	$outDelta *= 8;
	push(@inRates, $inDelta / $time);
 	push(@outRates, $outDelta / $time);
}


printf("Downstream: %dbps\nUpstream: %dbps\n", sum(@inRates)/@inRates, sum(@outRates)/@outRates);
$session->close;

exit 0;