Perl SNMP trap generator for scale testing? - perl

Question

I've hacked the script below together to let me generate traps to a test server. What I really need is something that will generate traps at a large scale so that I can check my tools on the receiving end to find out where the bottleneck is, such as UDP, Net::SNMP, Perl, etc.
I had hoped this script would let me generate something like 10k events/second but I am sadly mistaken.
Does anyone know if I can do this in Perl or have a suggestion of another way to do it?
#! /usr/bin/perl
use strict;
use warnings;
use Log::Fast;
use FindBin;
use Getopt::Long;
use File::Basename;
use Cwd qw(abs_path);
my $ROOT_DIR = abs_path("$FindBin::Bin/..");
use POSIX qw/strftime/;
use Net::SNMP qw(:ALL);
use Time::HiRes qw( time sleep );
#FIXME - I had to add below for Perl 5.10 users.
# on Perl 5.10, I would get the following when running:
# perl -e"autoflush STDOUT, 1;"
# Can't locate object method "autoflush" via package "IO::Handle" at -e line 1.
use FileHandle;
# Create default logger, will reconfigure it as soon as we read configuration from database
my $log = Log::Fast->global();
my $myname = $0;
$myname =~ s{.*/}{}; # leave just program name without path
# Command line options
my $options = {
debug => 0,
verbose => 0,
logfile => "./$myname.log",
help => 0,
community => "public",
trapsource => "127.0.0.1",
timelimit => 1,
};
sub usage_and_exit {
my ($exit_code) = #_;
print STDERR qq{
This program is used to generate SNMP traps to a specified host at a specified rate
Usage: $myname [-o --option]
-h : this (help) message
-d : debug level (0-5) (0 = disabled [default])
-v : Also print results to STDERR
-l : log file (defaults to local dir
-r : Rate (events/sec)
-ts : host to generate messages FROM
-td : host to generate messages TO
-tl : Run for this many seconds (default 1)
-c : community
Example: $myname -td 192.168.28.29 -r 1 -tl 5 -v
};
exit($exit_code);
}
GetOptions(
'debug|d=i' => \$options->{debug},
'help|h!' => \$options->{help},
'verbose|v!' => \$options->{verbose},
'logfile|l=s' => \$options->{logfile},
'rate|r=i' => \$options->{rate},
'trapsource|ts=s' => \$options->{trapsource},
'trapdest|td=s' => \$options->{trapdest},
'community|c=s' => \$options->{community},
'timelimit|tl=i' => \$options->{timelimit},
) or usage_and_exit(1); # got some invalid options
if ( $options->{help} ) {
usage_and_exit(0);
}
# Reconfigure log to use logfile (as we finally got it from $settings), also
# set proper level and output based on $options{verbose} and $options{debug}
setup_log();
# Finally we are initialized, announce this to the world :-)
$log->INFO("Program initialized successfully");
my $date = strftime "%Y-%m-%d %H:%M:%S", localtime;
# start func
my $period = 1 / $options->{rate};
my $start = time();
my $limit = time() + $options->{timelimit};
my $total = $options->{rate} * $options->{timelimit};
$log->INFO("Generating $options->{rate} trap(s) every second for $options->{timelimit} seconds (1 every $period seconds, $total total events)");
while($start < $limit) {
my $elapsed = time() - $start;
if ($elapsed < $period) {
sleep($period - $elapsed);
my ($session, $error) = Net::SNMP->session(
-hostname => $options->{trapdest},
-community => $options->{community},
-port => SNMP_TRAP_PORT, # Need to use port 162
-version => 'snmpv2c'
);
if (!defined($session)) {
$log->INFO("ERROR: %s.", $error);
exit 1;
}
my $result = $session->snmpv2_trap(
-varbindlist => [
'1.3.6.1.2.1.1.3.0', TIMETICKS, 600,
'1.3.6.1.6.3.1.1.4.1.0', OBJECT_IDENTIFIER, '1.3.6.1.4.1.326',
'1.3.6.1.6.3.18.1.3.0', IPADDRESS, $options->{trapsource}
]
);
if (!defined($result)) {
$log->INFO("ERROR: %s.", $session->error());
} else {
$log->INFO("SNMPv2-Trap-PDU sent from $options->{trapsource} to $options->{trapdest}.");
}
} else {
$start = time();
}
}
#-------------------------------------------
# There should only be subs from here down
#-------------------------------------------
# =================================================================================================
# Helper functions
# =================================================================================================
# commify not used yet
sub commify {
my $text = reverse $_[0];
$text =~ s/(\d\d\d)(?=\d)(?!\d*\.)/$1,/g;
return scalar reverse $text;
}
sub setup_log {
my $log_dir = dirname($options->{logfile});
# Create log dir, and build log path if not provided by command line option
if ( !-d $log_dir ) {
mkdir( $log_dir, 0755 ) or die("mkdir $log_dir: $!");
}
if ( !$options->{logfile} ) {
$options->{logfile} = $log_dir . "/" . basename( $0, '.pl' ) . '.log';
}
my $log_options = {};
# Set up output to file or both file and stderr
if ( $options->{verbose} ) {
# make multiplexer FH sending data both to file and STDERR
open( my $fh, '>>:tee', $options->{logfile}, \*STDERR )
or die("$options->{logfile}: $!");
$fh->autoflush(1);
$log_options->{fh} = $fh;
}
else {
open( my $fh, '>>', $options->{logfile} ) or die("$options->{logfile}: $!");
$log_options->{fh} = $fh;
}
# Setup extra information to put in every log line, depending on debug level
if ( $options->{debug} > 1 ) {
$log_options->{prefix} = "%D %T %S [%L] ";
}
else {
$log_options->{prefix} = "%D %T [%L] ";
}
$log_options->{level} = $options->{debug} > 0 ? 'DEBUG' : 'INFO';
$log->config($log_options);
$SIG{__WARN__} = sub {
my $msg = shift;
$msg =~ s/\n//;
$log->WARN($msg);
};
$log->INFO("Starting logging to $options->{logfile} with pid $$");
}
sub DEBUG {
my ( $level, #log_args ) = #_;
if ( $options->{debug} >= $level ) {
$log->DEBUG(#log_args);
}
}

Answer 1

Perhaps use something like Parallel::ForkManager ? In addition, with specific regard to testing scalability of your SNMP collector, you'll probably be interested in the use case of receiving the traps from many HOSTS, not just a single host sending traps at a high rate. For that, you might want to look at using pssh.
One problem might be the slowness of Net::SNMP in pure-perl - perhaps exectuting snmptest or snmptrap via the shell might be faster ? Worth a try.