fastnetmon

FastNetMon - High Performance Network Load Analyzer with PCAP/ULOG2 support

Why you write it?

It's reasonable question in the open source world.

Install

   # Debian 7 Wheezy
   apt-get install -y git libpcap-dev g++ gcc libboost-all-dev make
   # CentOS 6
   yum install -y git libpcap-devel gcc-c++ boost-devel boost make

   # If you need traffic counting
   apt-get install -y libhiredis-dev

   cd /usr/src
   git clone https://github.com/FastVPSEestiOu/fastnetmon.git
   cd fastnetmon

Select backend, we use ULOG2 as default, if you need PCAP u must change variable ENGINE in Makefile to PCAP

Compile it:

make

Start it:

./fastnetmon

Server configuration for PCAP: no configuration needed

Server configuration for ULOG2:

iptables -A FORWARD -i br0 -j ULOG --ulog-nlgroup 1 --ulog-cprange 32 --ulog-qthreshold 45

If you use PCAP, u can set monitored interface as command line parameter (u can set 'any' as inerface name but it work not so fine):

./fastnetmon br0

Example program screen:

Below you can see all clients with more than 2000 pps

Incoming Traffic    66167 pps 88 mbps
xx.yy.zz.15         3053  pps 0  Mbps
xx.yy.zz.248        2948  pps 0  Mbps
xx.yy.zz.192        2643  pps 0  Mbps

Outgoing traffic    91676 pps 728 mbps
xx.yy.zz.15         4471  pps 40  Mbps
xx.yy.zz.248        4468  pps 40  Mbps
xx.yy.zz.192        3905  pps 32  Mbps
xx.yy.zz.157        2923  pps 24  Mbps
xx.yy.zz.169        2809  pps 24  Mbps
xx.yy.zz            2380  pps 24  Mbps
xx.yy.zz            2105  pps 16  Mbps

Internal traffic    1 pps

Other traffic       25 pps

ULOG buffer errors: 2 (0%)
ULOG packets received: 19647

You can use this script for irq balancing on heavy loaded networks:

#!/bin/bash

# from http://habrahabr.ru/post/108240/
ncpus=`grep -ciw ^processor /proc/cpuinfo`
test "$ncpus" -gt 1 || exit 1

n=0
for irq in `cat /proc/interrupts | grep eth | awk '{print $1}' | sed s/\://g`
do
    f="/proc/irq/$irq/smp_affinity"
    test -r "$f" || continue
    cpu=$[$ncpus - ($n % $ncpus) - 1]
    if [ $cpu -ge 0 ]
            then
                mask=`printf %x $[2 ** $cpu]`
                echo "Assign SMP affinity: eth queue $n, irq $irq, cpu $cpu, mask 0x$mask"
                echo "$mask" > "$f"
                let n+=1
    fi
done

Author: Pavel Odintsov pavel.odintsov at gmail.com