Juniper SRX - Perl script - SNMP based RRDtool graphis from CPU usage and Flow Session (current)

Below is a simple perl script that queries queries a Juniper branch SRX box (210 in my case) for current data plance CPU usage as well as current flow numbers and creates RRDtool graphics based on the results.

Code:

# cat collect_srx_usage.pl 
#!/usr/bin/perl
# This script pols a Juniper SRX branch device for Current Flow sessions and Data Plane CPU usage.

use RRDs;

# RRD databases location 
my $rrd = '/var/home/www/static_pages/mrtg_graphs/rrd';
# images location 
my $img = '/var/home/www/static_pages/mrtg_graphs/images';

&MIBtoProcess("Sessions", "1.3.6.1.4.1.2636.3.39.1.12.1.1.1.6.0", "Current Flow Sessions");
&MIBtoProcess("CPU", "1.3.6.1.4.1.2636.3.39.1.12.1.1.1.4.0", "Current SPU Usage");


sub MIBtoProcess
{
   my $snmp = `snmpget -v2c -c public 10.12.1.2 $_[1] | awk '{print $NF}'`;
   #print "$snmp";
   my @snmp_array   = split / /, $snmp;
   my @r_snmp_array = reverse @snmp_array;
   $snmp = $r_snmp_array[0];
   #$snmp =~ s/[\x0A\x0D]//g;
   chomp($snmp);

   # create rrdtool database if it doesn't exist
   if (! -e "$rrd/$_[0].rrd")
   {
          print "creating rrd database for $_[0] object ...\n";
          RRDs::create "$rrd/$_[0].rrd",
               "-s 60",
               "DS:snmp:GAUGE:600:0:12500000",
               "RRA:AVERAGE:0.5:1:1440",
               "RRA:AVERAGE:0.5:5:2016",
               "RRA:AVERAGE:0.5:120:372",
               "RRA:AVERAGE:0.5:720:730";
   }

   # update RRD database
   RRDs::update "$rrd/$_[0].rrd", "N:$snmp";

   # generate graphs
   &genGraph($_[0], "day", $_[2]);
   &genGraph($_[0], "week", $_[2]);
   &genGraph($_[0], "month", $_[2]);
   &genGraph($_[0], "year", $_[2]);
}


sub genGraph
{
# subroutine for generating the graph
#         $_[0]: SNMP object
#         $_[1]: interval (day, week, month, year)
#         $_[2]: Object description

        RRDs::graph "$img/$_[0]-$_[1].png",
                "-s -1$_[1]",
                "-t Stats for SRX $_[0] :: $_[2] :: $_[1]",
                "--lazy",
                "-h", "80", "-w", "616",
                "-l 0",
                "-a", "PNG",
                "DEF:snmp=$rrd/$_[0].rrd:snmp:AVERAGE",
                "LINE1:snmp#0033CC",
                "GPRINT:snmp:MAX:  Max\\: %5.1lf ",
                "GPRINT:snmp:AVERAGE: Avg\\: %5.1lf %S",
                "GPRINT:snmp:LAST: Current\\: %5.1lf (avg)\\n",
                "HRULE:0#000000";
        if ($ERROR = RRDs::error) { print "$0: Error generating graph: $ERROR\n"; }
}

The script queries two OIDs using "snmpget" unix command ( see 'snmp' package ), parses the output and creates a RRD database if it is not created. Particularities of the rrd database is that it uses a 60 second step size (this indicates that the RRD database expects new values every 60 seconds). The "snmp" data source (DS) is "GAUGE": GAUGE does not save the rate of change. It saves the actual value itself. There are no divisions or calculations. Memory consumption in a server is a typical example of gauge

The graphic part is using a line to represent both values (AREA type can also be used, but I am interested in linear rrdtool graphic).

Graphics are created for last day, last week, last month and last year as seen in the structure.

Below is an example of such a graph (daily)

Attachment:

RRdtool-srx-cpu-usage-current-sessions.png [24.76 KiB]
Downloaded 1195 times

References: How to monitor CPU usage and flow sessions via SNMP - Juniper SRX Branch - 12.1X44http://forum.ivorde.ro/how-to-monitor-cpu-usage-and-flow-sessions-via-snmp-juniper-srx-branch-12-1x44-t14261.html
RRD tutorial http://oss.oetiker.ch/rrdtool/tut/rrd-beginners.en.html

Notes: the CPU usage is the same from Junos CLI command: "> show security monitoring fpc 0 " output line "CPU utilization : X %" and it represents the usage on the dataplane, not the control plane (routing engine).
Flow session represents the output from Junos CLI command: "> show security flow session summary".

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Juniper SRX - Perl script - SNMP based RRDtool graphis from CPU usage and Flow Session (current)

Juniper SRX - Perl script - SNMP based RRDtool graphis from CPU usage and Flow Session (current)