Skip to content


Switch branches/tags
This branch is 1741 commits ahead, 2927 commits behind pavel-odintsov:master.

Latest commit


Git stats


Failed to load latest commit information.
Latest commit message
Commit time


FastNetMon - A high performance DoS/DDoS load analyzer built on top of multiple packet capture engines (NetFlow, IPFIX, sFLOW, SnabbSwitch, netmap, PF_RING, PCAP).

What can we do? We can detect hosts in our own network with a large amount of packets per second/bytes per second or flow per second incoming or outgoing from certain hosts. And we can call an external script which can notify you, switch off a server or blackhole the client.

License: GPLv2

Author: Pavel Odintsov pavel.odintsov at Follow my Twitter


Supported packet capture engines

  • NetFlow v5, v9
  • sFLOW v4 (dev branch only), v5
  • Port mirror/SPAN capture with PF_RING (with ZC/DNA mode support need license), SnabbSwitch, NETMAP and PCAP

You could look comparison table for all available packet capture engines.


  • Complete BGP Flow Spec support, RFC 5575
  • Can process incoming and outgoing traffic
  • Can trigger block script if certain IP loads network with a large amount of packets/bytes/flows per second
  • Thresholds could be configured in per subnet basis with hostgroups feature
  • Could announce blocked IPs to BGP router with ExaBGP
  • GoBGP integration for unicast IPv4 announces
  • Full integration with Graphite and InfluxDB
  • Redis integration
  • MongoDB integration
  • Deep packet inspection for attack traffic
  • netmap support (open source; wire speed processing; only Intel hardware NICs or any hypervisor VM type)
  • SnabbSwitch support (open source, very flexible, LUA driven, very-very-very fast)
  • Could filter out NetFLOW v5 flows or sFLOW packets with script implemented in LUA (useful for port exclude)
  • Supports L2TP decapsulation, VLAN untagging and MPLS processing in mirror mode
  • Can work on server/soft-router
  • Can detect DoS/DDoS in 1-2 seconds
  • Tested up to 10GE with 12 Mpps on Intel i7 3820 with Intel NIC 82599
  • Complete plugin support
  • Could capture attack fingerprint in pcap format
  • Have complete support for most popular attack types

Running Fastnetmon

Supported platforms

  • Linux (Debian 6/7/8, CentOS 6/7, Ubuntu 12+)
  • FreeBSD 9, 10, 11
  • Mac OS X Yosemite

Supported architectures

  • x86 64 bit (recommended)
  • x86 32 bit

Router integration instructions:

Distributions Supported

Build Status Gitter Stories in Progress What is "flow" in FastNetMon terms? It's one or multiple udp, tcp, icmp connections with unique src IP, dst IP, src port, dst port and protocol.


Main program screen image:

Main screen image

Example for cpu load on Intel i7 2600 with Intel X540/82599 NIC on 400 kpps load: Cpu consumption

Example deployment scheme: Network diagramm

Example of notification email about detected attack.

To enable sFLOW simply specify IP of server with installed FastNetMon and specify port 6343. To enable netflow simply specify IP of server with installed FastNetMon and specify port 2055.

Why did we write this? Because we can't find any software for solving this problem in the open source world!

How I can help project?

  • We are looking for maintainer for Debian and Fedora/EPEL packages
  • Test it!
  • Share your experience
  • Share your use cases
  • Share your improvements
  • Test it with different equipment
  • Create feature requests


This is old freezed version! Please use for actual but unstable code







No packages published


  • C++ 69.9%
  • C 16.4%
  • Perl 8.1%
  • CMake 2.1%
  • Shell 0.8%
  • Lua 0.7%
  • Other 2.0%