Open Source C++ Network Monitoring Software for Linux

Angry IP scanner is fast and friendly network scanner for Windows, Linux, and Mac. It is very extensible, allowing it to be used for very wide range of purposes, with the primary goal of being useful to network administrators.

Pandora FMS is an enterprise-ready monitoring solution that provides unparalleled flexibility for IT to address both immediate and unforeseen operational issues, including infrastructure and IT processes. It uniquely enables business and IT to adapt to changing needs through a flexible and rapid approach to IT and business deployment. Pandora FMS consolidates all the needs of modern monitoring (ITOM, APM, BAM) and provides status and performance metrics from different operating systems, cloud, virtual infrastructure (VMware, Hyper-V, XEN), Docker containers, applications, storage and hardware devices such as firewalls, proxies, databases, web servers or routers. It's highly scalable (up to 2000 nodes with one single server), 100% web and with multi-tenant capabilities. It has a very flexible ACL system and several different graphical reports and user-defined control screens.

VoIPmonitor is open source network packet sniffer with commercial frontend for SIP SKINNY MGCP RTP and RTCP VoIP protocols running on linux. VoIPmonitor is designed to analyze quality of VoIP call based on network parameters - delay variation and packet loss according to ITU-T G.107 E-model which predicts quality on MOS scale. Calls with all relevant statistics are saved to MySQL or ODBC database. Optionally each call can be saved to pcap file with either only SIP / SKINNY protocol or SIP/RTP/RTCP/T.38/udptl protocols. VoIPmonitor can also decode audio.

NSClient++ is a windows service that allows performance metrics to be gathered by Nagios (and possibly other monitoring tools). It is an attempt to create a NSClient and NRPE compatible but yet extendable performance service for windows.

Icinga is a monitoring system that checks the availability of your network resources, notifies users of outages, and generates performance data for reporting. Scalable and extensible, Icinga can monitor large, complex environments across multiple locations. This includes your data center as well as your private, public, or hybrid clouds. Icinga 2 is the monitoring server and requires Icinga Web 2 on top in your Icinga Stack. The configuration can be easily managed with either the Icinga Director, config management tools, or plain text within the Icinga DSL.

SBLIM (pronounced "sublime"), the Standards Based Linux Instrumentation for Manageability is an IBM-initiated Open Source project, intended to enhance the manageability of GNU/Linux systems. It does so by enabling WBEM, Web Based Enterprise Management.

Osquery is an operating system instrumentation framework for Windows, OS X (macOS), Linux, and FreeBSD. The tools make low-level operating system analytics and monitoring both performant and intuitive. Osquery exposes an operating system as a high-performance relational database. This allows you to write SQL queries to explore operating system data. With osquery, SQL tables represent abstract concepts such as running processes, loaded kernel modules, open network connections, browser plugins, hardware events or file hashes.Osquery queries your devices like a database. Osquery uses basic SQL commands to leverage a relational data-model to describe a device. Frequently, attackers will leave a malicious process running but delete the original binary on disk. This query returns any process whose original binary has been deleted, which could be an indicator of a suspicious process.

Zeek has a long history in the open source and digital security worlds. Vern Paxson began developing the project in the 1990s under the name “Bro” as a means to understand what was happening on his university and national laboratory networks. Vern and the project’s leadership team renamed Bro to Zeek in late 2018 to celebrate its expansion and continued development. Zeek is not an active security device, like a firewall or intrusion prevention system. Rather, Zeek sits on a “sensor,” a hardware, software, virtual, or cloud platform that quietly and unobtrusively observes network traffic. Zeek interprets what it sees and creates compact, high-fidelity transaction logs, file content, and fully customized output, suitable for manual review on disk or in a more analyst-friendly tool like a security and information event management (SIEM) system.

A java wrapper for popular "libpcap" and "WinPcap" libraries. Accurate full API translation. Packet buffers delivered with no copies. Send custom packets, gather statistics. Comprehensive and easily extensible DPI engine.

Conky is a free, light-weight system monitor for X, that displays any kind of information on your desktop. Conky is free software and runs in X on Linux and BSD. Originally a fork of Torsmo, Conky's torsmo-based code is BSD licensed. New code in Conky has been licensed under GPL 3.0. Since its inception, Conky has changed significantly from its predecessor, while maintaining simplicity and configurability. Conky can display just about anything, either on your root desktop, in its own window. Not only does Conky have many built-in objects, it can also display just about any piece of information by using scripts and other external programs. A plethora of OS stats (uname, uptime, CPU usage, mem usage, disk usage, "top" like process stats, and network monitoring, just to name a few). Conky can display information either as text, or using simple progress bars and graph widgets, with different fonts and colours.

nload is a console application which monitors network traffic and bandwidth usage in real time. It visualizes the in- and outgoing traffic using two graphs and provides additional info like total amount of transfered data and min/max network usage.

phpLDAPadmin is a web-based LDAP administration tool for managing your LDAP server. With it you can browse your LDAP tree, view LDAP schema, perform searches, create, delete, copy and edit LDAP entries. You can even copy entries between servers.

Yconalyzer is a low-overhead pcap utility that provides a bird's eye view of traffic on a particular TCP port, displaying a distribution of duration, volume and throughput over all connections while being able to narrow down to a connection as well.

"Open Source Tripwire® has now moved to https://github.com/Tripwire/tripwire-open-source. Open Source Tripwire® software is a security and data integrity tool useful for monitoring and alerting on specific file change(s) on a range of systems. The project is based on code originally contributed by Tripwire, Inc. in 2000. "

A utility for detecting and resisting BIDIRECTIONAL ARP spoofing. It can anti-spoof for not only the local host, but also other hosts in the same subnet. It is as well a handy helper for gateways which don't work well with ARP.

qtmib is an easy-to-use SNMP MIB Browser based on QT4 library. It is build as a front-end for net-snmp tools, and it allows the user to query any SNMP enabled device. It supports SNMPv1 and SNMPv2c. qtmib is released under GPL v2 license.

Netmap can be used to make a graphical representation of the surounding network. It first uses traceroute to make a list of all routers and their interconnections, after which it generates a .dot file. You need the Dotty program to view the graphical rep

This is a Docsis cable modem diagnostic tool for Linux and FreeBSD, it can get information from Docsis 1.0 , 1.1 and 2.0 cable modems. It gathers information from the cable modem via SNMP and displays various cable parameters in real time.

Why to pay tens of thousands $$$ for your network management software? Get visibility into your networks and complex processes inside with NG-NetMS now! NG-NetMS is a new end-to-end network management platform for your Linux servers, Cisco, Juniper, HP and Extreme routers, switches and firewalls. NG-NetMS is precise, quick and efficient. It collects most complete information about the network inventory, topology, map of IPv4 addresses quickly and with minimum hassle. Most important you will be able to collect, process and analyse Syslog events and SNMP alarms both in near-real-time and from the historical archives in a new way. We successfully used NG-NetMS for delivery of network assessment services for our customers worldwide for many years. And now we want to share this unique and fully functional tool with community. It is not capped in terms of performance or number of nodes. The only limit is the hardware you deploy it on. http://www.opt-net.eu/

A real-time packet sniffer / analyzer for Dark Age of Camelot (DAoC).

Psniff is a packet sniffer and spoofer based on the PF_PACKET protocol family provided in kernel >=2.0 . Some of the protocols initially supported are IPV4,IPV6,TCP,UCP,BGP,ICMP,RIP, NTP.

glFlow is a robust, fast, portable, pcap-centric (D)DoS detection tool.

IP Tables State implements the "state top" feature from IP Filter for IP Tables. "State top" displays the states held by your stateful firewall in a "top"-like manner, in real time. IPTState also has an option to print your state table once and NOTE: Development has moved to github: http://github.com/jaymzh/iptstate

openSNMP is a multi-threaded SNMPv3 engine. This project supports the Simple Network Management Protocol version 3. In particular, it is designed to match the architecture of the Internet Engineering Task Force SNMPv3 standard (RFCs 3410-15).

Traffic Monitor for LAN is a tool for monitoring and limiting network traffics generated by every user in LAN. Run it on the gateway PC.