Free monitoring and controlling software for linux

Remote Monitoring Agent (RMA in short) is an auxiliary application for HostMonitor. Enterprise license for Advanced Host Monitor already includes license for 10 installations of the agent. Holders of a Lite, Standard or Professional licenses may buy an additional license for Remote Monitoring Agent separately.
HostMonitor 4.0+ can monitor remote networks using Remote Monitoring Agents (RMA). RMA is small application that accepts requests from HostMonitor, performs test and provides information about test result back to HostMonitor.
Why you may need RMA? Here are just several reasons:
RMA increases security of the network. When you have to run the tests such as CPU Usage test or Performance Counters tests on a remote Windows system, HostMonitor must be able to log in to that system with administrators privileges. Instead you may now use an agent installed on that remote system. In this case HostMonitor will not have to log on to that system at all. HostMonitor needs just one TCP port to communicate with the RMA agent (by default it uses #1055 port, however you may set an agent to use any other port).
Remote Monitoring Agent is also a very useful tool when you have to monitor two (or many) separated networks (connected through Internet). In this case installing just one instance of RMA behind the firewall in network "A" will allow to monitor entire network "A" using the HostMonitor located in the network "B" with just one open TCP port.
RMA decreases the network traffic. E.g. frequent use of "File Integrity" or "Compare Files" tests in an array of remote systems may apply significant load on the network. The more and the bigger files you test the more traffic increase you get. RMA runs locally and sends only the test results to the HostMonitor thus decreasing the amount of network traffic.
Remote Monitoring Agent simplifies network administration. You no longer need to share local drives/folders to perform tests such as File Integrity, Folder/File Size, File Availability, Count Files, etc
RMA for Linux / BSD / Solaris allows you to perform tests that HostMonitor cannot perform. For example HostMonitor cannot monitor processes that are running on Linux systems. RMA can do that.
Main features:
- All traffic between Remote Monitoring Agents and HostMonitor is encrypted.
- It is possible to customize the list of enabled tests for each of the agents (e.g. living only Count Files and UNC tests only).
- You can restrict incoming TCP connections with the list of acceptable addresses.
- With RMA Manager you may configure, restart and even upgrade agent(s) remotely.

Monitoring API project is a multi-user programming interface designed to simplify the development of network monitoring software and allows users to express their monitoring needs in a device-independent way.
The main abstraction provided by MAPI is the network flow. Although flows have been used before in network monitoring systems, MAPI gives flows a first-class status. Applications that uses MAPI can specify what flows or flow statistics they are interested in by applying functions to flows.
A MAPI function can be a BPF filter, string search, packet counter or more advanced like a NetFlow generator. These function will automatically run in hardware if there is support for it on the hardware being used.
MAPI currently supports the following hardware:
- Normal NICs through libpcap
- DAG cards without co-processor
- SCAMPI adapter
Enhancements:
- This release includes support for distributed monitoring, several new MAPI functions, demo applications, and a lot of bugfixes.

Argus Monitoring System software is a system and network monitoring application.
It will monitor nearly anything you ask it to monitor (TCP + UDP applications, IP connectivity, SNMP OIDS, Programs, Databases, etc).
It presents a nice clean, easy to view web interface that will keep both the managers happy (Red Bad. Green Good.) and the techs happy ("Ah! thats what the problem is").
It can send alerts numerous ways (such as via pager) and can automatically escalate if someone falls asleep.
Main features:
- It is open-source available at no charge.
- It has a clean and intuitive web interface.
- The web pages can easily be understood by non-technical people.
- It can generate graphs of what is going on.
- It can monitor network connectivity (Ping test)
- It can monitor TCP/UDP ports
- It can monitor a wide variety of TCP/UDP applications (HTTP, SMTP, RADIUS, ...)
- It can monitor the output or exit code of a program (Program test)
- It can monitor the content of a web page (such as a shopping cart application)
- It can monitor the authoritativeness of a nameserver
- It can monitor SNMP OIDs (such as BGP status, UPS voltage, room temperature, ...)
- It can monitor the results of SQL queries
- It can monitor itself.
- It can be extended to monitor things that the author didnt think of
- It can notify someone (or many people) when something happens
- It can escalate, and notify someone else, if things dont get fixed.
- It can not alarm for known downtime (maintenance overrides)
- It will summarize and rate-limit multiple notifications to prevent paging-floods.
- It keeps historical statistics, for analysis or SLA verification.
- It scales well and can monitor many, many things.
- It can restrict users to viewing only certain items (user "views")
- It can restrict users access to certain features (access control)
- It can support IPv6.
- It can support SNMPv3.
- It can support l10n for your native language.
- It can support redundant multi-server configurations.
Enhancements:
- This release offers improved performance and scalability, adds support for additional tests, and adds support for failover and redundancy.

Ops Control Panel is a frontend for MRTG.

Unlike many other frontends, it does not have any requirements beyond those of MRTG, although it can support PHP-enabled Web servers instead of just running as a Perl CGI script.

Ops Control Panel project provides overviews of MRTG-based monitoring pages in a variety of formats.

active acoustic vibration control tool is a set of basic tools for monitoring and modulating audio noise.

The tools aim toward a set of codes and algorithms for monitoring noise signal and modulation and reducing them using active noise control priciples.

Active noise control and soundproofing is a relativly recent development (first researched around 30 years ago), and has been in constant development for many and varied situations and applications.

The basic concept of active noise control is the aplication of equal and opposite force to cancel out vibration.

The project attempts to provide a starting point and library for experimentation into various methods of digital signal processing for active noise reduction and soundproofing.

Noise cancellation has been used in many environments currently active control is best used in constant vibrations with lower frequencys.

The principle is of controlling the noise level by adding an equal and opposite sound to the noise in the environment. The basic principle may be simple but the actual effectivness depends on many environmental factors.

Generally simplistic out of phase sound wave is used which works to some extent and requires little processing (a simple XOR with -1) this will tend to leave a large number of artifacts as the amplitude of higher frequency components (above i->o delay time) rises.

i->o processing delay
e transducer efficiency
p sound propagation characteristics
r reflections

The project aims to provide a framework for many dsp architectures, dac/adc chips, transducers and monitors.

Create tools for acoustic calibration and data logging hardware
To simplify implementation of active noise and vibration control systems.
To provide an open source standard for use within the industry and education.
To encourage hardware producers to distribute standard interface descriptions for their hardware
Enable low cost development of systems using COTS consumer hardware for noise and vibration control.

HLDS Control Panel is a php based web app to start a Half-life dedicated server (hlds) and any of its mod games (CS, DOD) using a web browser.
Form driven for ease of use, and no need for shell access. Includes mapcycle admin, for editing mapcycle.txt. Written on Linux/PHP4
Main features:
- Start/Stop server
- View/Purge the build up of game log files
- View/Edit/Shuffle Mapcycles
- Server monitoring page
- Email notify when a game is started
- Limit how many game instances users can start (by port number)
- Steam web gui for updating/installing steam games (dedicated servers only)
- Remote listener for starting up games on other servers

DDCcontrol is a program used to control monitor parameters, like brightness and contrast, by software, i.e. without using the OSD (On Screen Display) and the buttons in front of the monitor.
With DDCcontrol you can monitor the parameters of your monitor on Linux.
Enhancements:
- This release mainly adds support for many new monitors, and fixes some minor bugs.