#!/usr/bin/perl

##
## Drano v0.1 written 032415 by Bowie Poag
##
## Drano makes sure the pipes are clear by reporting when network buffers have been depleted.
## This script is designed to be run as root on a VIO server.
##
## It also requires a little tuning on your part -- Replace any instance of "ent12" with the adapter of your choice.
##

$DEBUG=0;
$threshold=$ARGV[0] || 90;
$problemTiny="NO";
$problemSmall="NO";
$problemMedium="NO";
$problemLarge="NO";
$problemHuge="NO";

print "\nDrano: Spinning up..\n";
print "Drano: Collecting netstat dump..\n";
print "Drano:\n";
@netstatDump=`netstat -v ent12 2>/dev/null`;

foreach $item (@netstatDump)
{
        chomp($item);
        $item=~s/^\s+//g;

        if ($item=~/Max Buffers/)
        {
                print "Drano: $item\n";
                $item=~s/\s+/ /g;
                @line=split(" ",$item);
                $maxTiny=$line[2];
                $maxSmall=$line[3];
                $maxMedium=$line[4];
                $maxLarge=$line[5];
                $maxHuge=$line[6];
        }

        if ($item=~/Allocated/ && $item!~/Max/)
        {
                print "Drano: $item\n";
                $item=~s/\s+/ /g;
                @line=split(" ",$item);
                $alcTiny=$line[1];
                $alcSmall=$line[2];
                $alcMedium=$line[3];
                $alcLarge=$line[4];
                $alcHuge=$line[5];
        }


}

print "Drano:\n";

$DEBUG && print "MxT:[$maxTiny] MxS:[$maxSmall] MxM:[$maxMedium] MxL:[$maxLarge] MxH:[$maxHuge]\n";
$DEBUG && print "AlT:[$alcTiny] AlS:[$alcSmall] AlM:[$alcMedium] AlL:[$alcLarge] AlH:[$alcHuge]\n";

print "Drano: Analyizing buffer stats..\n";
print "Drano:\n";

$conTiny=sprintf("%-2.2f",($alcTiny/$maxTiny)*100);
$conSmall=sprintf("%-2.2f",($alcSmall/$maxSmall)*100);
$conMedium=sprintf("%-2.2f",($alcMedium/$maxMedium)*100);
$conLarge=sprintf("%-2.2f",($alcLarge/$maxLarge)*100);
$conHuge=sprintf("%-2.2f",($alcHuge/$maxHuge)*100);

if ($conTiny > $threshold)
{
        $problemTiny="YES";
}

if ($conSmall > $threshold)
{
        $problemSmall="YES";
}

if ($conMedium > $threshold)
{
        $problemMedium="YES";
}

if ($conLarge > $threshold)
{
        $problemLarge="YES";
}

if ($conHuge > $threshold)
{
        $problemHuge="YES";
}

printf("%-16s %16s %16s %11s\n","Drano: Buffer Size","Consumption (%)","Threshold (%)","Problem?");
printf("%-16s %16s %16s %11s\n","Drano: -----------","---------------","-------------","--------");
printf("%-16s %16f %16f %11s\n","Drano: Tiny","$conTiny","$threshold","$problemTiny");
printf("%-16s %16f %16f %11s\n","Drano: Small","$conSmall","$threshold","$problemSmall");
printf("%-16s %16f %16f %11s\n","Drano: Medium","$conMedium","$threshold","$problemMedium");
printf("%-16s %16f %16f %11s\n","Drano: Large","$conLarge","$threshold","$problemLarge");
printf("%-16s %16f %16f %11s\n","Drano: Huge","$conHuge","$threshold","$problemHuge");
print "Drano:\n";


if ($problemTiny ne "YES" && $problemSmall ne "YES" && $problemMedium ne "YES" && $problemLarge ne "YES" && $problemHuge ne "YES")
{
        print "Drano: Everything looks fine. All your buffer consumption percentages are below the given threshold of $threshold"."%".".\n";
       
}
else
{
        print "Drano: Looks like you've run out of network buffers on one or more fronts. Time to tune up.\n";
        system("logger Drano Warning - Partial network buffer overflow detected. Network interface requires additional tuning.");
}