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--- pages:howtos:diagnose:linux-diagnosis-and-monitoring-tools [2022/02/07 11:20] – mischerh
+++ pages:howtos:diagnose:linux-diagnosis-and-monitoring-tools [2023/06/15 16:42] (current) – [mytop] mischerh
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-{{tag>howto linux monitoring tools top htop atop netatop apache apachetop modstatus proftp ftptop mytop mysql mariadb powertop iotop ntopng iftop jnettop bandwidthd etherape ethtool nethogs iptraf ngrep mrtg bmon traceroute traceroute6 tracert6 iptstate darkstat vnstat netstat ss nmap mtr tcpdump justniffer serverdensity}}
+{{tag>howto linux windows aix diagnosis monitoring tools top htop atop netatop apache apachetop modstatus proftp ftptop mytop mysql mariadb powertop iotop ntopng iftop jnettop bandwidthd etherape ethtool nethogs iptraf ngrep mrtg bmon traceroute traceroute6 tracert6 iptstate darkstat vnstat netstat ss nmap mtr tcpdump justniffer serverdensity opennms sysusage pcp ksysguard munin nagios icinga zenoss cacti zabbix nmon conky glances squid sarg saidar libstatgrab rrdtool procexp linuxprocessexplorer df dstat netsnmp incron monitorix vmstat mpstat pmap uptime ps sar sysstat iostat collectl free goaccess logwatch swatchdog multitail}}
 FIXME
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   * https://github.com/JeremyJones/Apachetop
   * https://github.com/JeremyJones/Apachetop/wiki
-apachetop is a console-based (non-gui) tool for monitoring the threads and overall performance of a set of Apache web servers. It runs on Unix systems which have Perl, LWP, and Term::ReadKey installed. It is based largely on the excellent mytop tool written by Jeremy Zawodny.
+apachetop is a console-based (non-gui) tool for monitoring the threads and overall performance of a set of Apache web servers. It runs on Unix systems which have Perl, LWP, and <nowiki>Term::ReadKey</nowiki> installed. It is based largely on the excellent mytop tool written by Jeremy Zawodny.
 ===== Apache mod_status =====
@@ Line 58: / Line 58: @@
   * https://jeremy.zawodny.com/mysql/mytop/
   * https://jeremy.zawodny.com/mysql/mytop/mytop.html
-mytop is a console-based (non-gui) tool for monitoring the threads and overall performance of a MySQL 3.22.x, 3.23.x, and 4.x server. It runs on most Unix systems (including Mac OS X) which have Perl, DBI, and Term::ReadKey installed. And with Term::ANSIColor installed you even get color. If you install Time::HiRes, you'll get good real-time queries/second stats. As of version 0.7, it even runs on Windows (somewhat).
+mytop is a console-based (non-gui) tool for monitoring the threads and overall performance of a MySQL 3.22.x, 3.23.x, and 4.x server. It runs on most Unix systems (including Mac OS X) which have Perl, DBI, and <nowiki>Term::ReadKey</nowiki> installed. And with <nowiki>Term::ANSIColor</nowiki> installed you even get color. If you install Time::HiRes, you'll get good real-time queries/second stats. As of version 0.7, it even runs on Windows (somewhat).
 ===== powertop =====
@@ Line 197: / Line 197: @@
 OpenNMS is a free and open-source enterprise grade network monitoring and network management platform. It is developed and supported by a community of users and developers and by the OpenNMS Group, offering commercial services, training and support. The goal is for OpenNMS to be a truly distributed, scalable management application platform for all aspects of the FCAPS network management model while remaining 100% free and open source. Currently the focus is on Fault and Performance Management. All code associated with the project is available under the Affero General Public License. The OpenNMS Project is maintained by The Order of the Green Polo.
+===== SysUsage =====
+  * https://github.com/darold/sysusage
+  * https://sysusage.darold.net/
+SysUsage: the sysstat and sar grapher. SysUsage is a tool used to continuously monitor a system and generate daily/weekly/monthly/yearly graphical report using rrdtool and sar. SysUsage generate graphical reports on all system activity information. His periodical reports allow you to keep track of the machine activity during his life and will be a great help for performance analysis and resources management. SysUsage can be run periodically from 10 seconds cycle in daemon mode to 1 minute or more using crond. SysUsage can be run from a central server to call a ssh remote execution of the sysusage perl script so that collected data will be stored in this central place. You also will have just one place where rrdtool and related Perl modules need to be installed as well as just one place where sysusagegraph or sysusagejqgraph need to be executed.
+SysUsage continuously monitor your systems informations and generate periodical graph reports using rrdtool or javascript jqplot library. All reports are shown throught a web interface.
+SysUsage grabs all system activities using Sar and system commands allowing you to keep tracks of your computer or server activity during his life. It is a great help for performance analysis and resources management. The threshold notification can alarm you when the system capabilities are reached by sending SMTP messages or throught Nagios reports.
-SysUsage
+By default it will monitor all you need to know on your server activity (See Features), it is written in Perl and should works on all Unix like plateforms. It doesn't require a Database system like MySQL or PostgreSQL but lie on rrdtool. In addition you can embeded your own plugins written in any programing language.
-~\ownCloud\zim\Bilder\DEF\artikel-linux-monitoring-tools\sysusage.jpg
+Since release 5.0 SysUsage can be run from a centralized place where collected statistics will be stored and where graphics will be rendered. Unless other monitoring tools with lot of administration work, SysUsage is design to have the lesspossible things to configure and a high level of admin system knowledge. Each server can also be self monitored and you just have to connect your browser to the web interface to know his health level.
-SysUsage monitors your system continuously via Sar and other system commands. It also allows notifications to alarm you once a threshold is reached. SysUsage itself can be run from a centralized place where all the collected statistics are also being stored. It has a web interface where you can view all the stats.
+SysUsage is design with simplicity in mind. I want all relevant statistics from my servers within an intuitive web interface and without spending too much time to configure it, if you know Nagios, you know what I mean. You will especially like SysUsage for that.
-* http://sysusage.darold.net/
+===== PCP =====
+  * http://www.pcp.io/
+  * https://github.com/performancecopilot/pcp
+PCP - Performance Co-Pilot. Performance Co-Pilot is a system performance analysis toolkit. Lightweight : Collect performance metrics from your systems efficiently. Distributed : Collate metrics from multiple hosts and a variety of operating systems. Included : Everything you need is already included in the major distributions: Fedora, RHEL, Debian, SUSE, Ubuntu, Gentoo.  Analyze systems' performance metrics in real-time or using historical data. Compare performance metrics between different hosts and different intervals. Observe trends and identify abnormal patterns.  Extend the collected performance metrics in a simple way. PCP offers a multitude of APIs and libraries to extract and make use of performance metrics from your own application.
-brainypdm
+===== KDE system guard =====
+  * https://apps.kde.org/ksysguard/
+System Guard allows you to monitor information and statistics about your system. In addition to monitoring the local system, it can connect to remote systems running the System Guard Daemon.
-~\ownCloud\zim\Bilder\DEF\artikel-linux-monitoring-tools\brainypdm.jpg
+===== Munin =====
+  * https://munin-monitoring.org/
+  * https://guide.munin-monitoring.org/en/latest/
+Munin is a networked resource monitoring tool that can help analyze resource trends and "what just happened to kill our performance?" problems. It is designed to be very plug and play. A default installation provides a lot of graphs with almost no work. In Norse mythology Hugin and Munin are the ravens of the god king Odin. They flew all over Midgard for him, seeing and remembering, and later telling him. "Munin" means "memory".
-brainypdm is a data management and monitoring tool that has the capability to gather data from nagios or another generic source to make graphs. It’s cross-platform, has custom graphs and is web based.
+===== Nagios =====
-* http://sourceforge.net/projects/brainypdm/
+  * https://www.nagios.org/
+  * https://github.com/NagiosEnterprises/nagioscore
+Nagios Core /ˈnɑːɡiːoʊs/, formerly known as Nagios, is a free and open-source computer-software application that monitors systems, networks and infrastructure. Nagios offers monitoring and alerting services for servers, switches, applications and services. It alerts users when things go wrong and alerts them a second time when the problem has been resolved.
+Ethan Galstad and a group of developers originally wrote Nagios as NetSaint. As of 2015 they actively maintain both the official and unofficial plugins. Nagios is a recursive acronym: "Nagios Ain't Gonna Insist On Sainthood" – "sainthood" makes reference to the original name NetSaint, which changed in response to a legal challenge by owners of a similar trademark. "Agios" (or "hagios") also transliterates the Greek word άγιος, which means "saint".
-PCP
+Nagios was originally designed to run under Linux, but it also runs on other Unix variants. It is free software licensed under the terms of the GNU General Public License version 2 as published by the Free Software Foundation.
+Network Monitoring: When it comes to open source network monitoring tools, the World’s largest organizations turn to Nagios. Nagios monitors the network for problems caused by overloaded data links or network connections, as well as monitoring routers, switches and more. Easily able to monitor availability, uptime and response time of every node on the network, Nagios can deliver the results in a variety of visual representations and reports. Network Monitoring Software. Network Traffic Monitoring. Network Analyzer.
-~\ownCloud\zim\Bilder\DEF\artikel-linux-monitoring-tools\pcp.jpg
+Nagios is known for being the best server monitoring software on the market. Server monitoring is made easy in Nagios because of the flexibility to monitor your servers with both agent-based and agentless monitoring. With over 5000 different addons available to monitor your servers, the community at the Nagios Exchange have left no stone unturned. Server Monitoring Software. Windows Server Monitoring. Linux Server Monitoring.
-PCP has the capability of collating metrics from multiple hosts and does so efficiently. It also has a plugin framework so you can make it collect specific metrics that is important to you. You can access graph data through either a web interface or a GUI. Good for monitoring large systems.
+Implementing effective application monitoring with Nagios allows your organization to quickly detect application, service, or process problems, and take action to eliminate downtime for your application users. Nagios provides tools for monitoring of applications and application state – including Windows applications, Linux applications, UNIX applications, and Web applications. Application Monitoring Tools. Web Application Monitoring. Application Log Monitoring.
-* http://www.pcp.io/
+===== Icinga =====
+  * https://github.com/Icinga/icinga2
+  * https://icinga.com/docs/icinga-2/latest/doc/02-installation/
+  * https://icinga.com/
+Icinga is a monitoring system which 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. 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.
-KDE system guard
+===== Zenoss =====
+  * https://community.zenoss.com/
+Zenoss Community Edition is a free and open-source application, server, and network management platform based on the Zope application server. Released under the GNU General Public License version 2, Zenoss Community Edition provides a web interface that allows system administrators to monitor availability, inventory/configuration, performance, and events. Zenoss Community Edition is by Zenoss Inc., which was founded in 2005 and is headquartered in Austin, Texas. The company develops hybrid IT monitoring and analytics software.
-~\ownCloud\zim\Bilder\DEF\artikel-linux-monitoring-tools\kdesystemguard.jpg
+===== Cacti =====
+  * https://www.cacti.net/
+  * https://github.com/Cacti/cacti
+  * https://docs.cacti.net/
+Cacti is an open-source, web-based network monitoring and graphing tool designed as a front-end application for the open-source, industry-standard data logging tool RRDtool. Cacti allows a user to poll services at predetermined intervals and graph the resulting data. It is generally used to graph time-series data of metrics such as CPU load and network bandwidth utilization. A common usage is to monitor network traffic by polling a network switch or router interface via Simple Network Management Protocol (SNMP).
-This tool is both a system monitor and task manager. You can view server metrics from several machines through the worksheet and if a process needs to be killed or if you need to start a process it can be done within KDE system guard.
+The front end can handle multiple users, each with their own graph sets, so it is sometimes used by web hosting providers (especially dedicated server, virtual private server, and colocation providers) to display bandwidth statistics for their customers. It can be used to configure the data collection itself, allowing certain setups to be monitored without any manual configuration of RRDtool. Cacti can be extended to monitor any source via shell scripts and executables.
-* https://userbase.kde.org/KSysGuard
+Cacti can use one of two back ends: "cmd.php", a PHP script suitable for smaller installations, or "Spine" (formerly Cactid), a C-based poller which can scale to thousands of hosts.
-Munin
+===== Zabbix =====
+  * https://git.zabbix.com/projects/zbx/repos/zabbix/browse
+  * https://www.zabbix.com/
+Zabbix is an open-source monitoring software tool for diverse IT components, including networks, servers, virtual machines (VMs) and cloud services. Zabbix provides monitoring metrics, among others network utilization, CPU load and disk space consumption. Zabbix monitoring configuration can be done using XML based templates which contain elements to monitor.[3] The software monitors operations[vague] on Linux, Hewlett Packard Unix (HP-UX), Mac OS X, Solaris and other operating systems (OSes); however, Windows monitoring is only possible through agents. Zabbix can use MySQL, MariaDB, PostgreSQL, SQLite, Oracle or IBM DB2 to store data.[4]
-Munin is also a web interface GUI for RRDtool, it was written in Perl and licensed under GPL, Munin is a good tool to monitor systems, networks, applications and services. It works on all Unix-like operating systems and has a nice plugin system; there are 500 different plugin available to monitor anything you want on your machine. A notifications system is available to send messages to the administrator when there’s an error or when the error is resolved.
+Backend of Zabbix is written in C and the web frontend is written in PHP.
-~\ownCloud\zim\Bilder\DEF\artikel-linux-monitoring-tools\munin.jpg
+Zabbix offers several monitoring features:
+  * Simple checks can verify the availability and responsiveness of standard services such as SMTP or HTTP without installing any software on the monitored host.
+  * A Zabbix agent can also be installed on UNIX and Windows hosts to monitor statistics such as CPU load, network utilization, disk space, etc.
+  * As an alternative to installing an agent on hosts, Zabbix includes support for monitoring via SNMP, TCP and ICMP checks, as well as over IPMI, JMX, SSH, Telnet and using custom parameters. Zabbix supports a variety of near-real-time notification mechanisms, including XMPP.
-~\ownCloud\zim\Bilder\DEF\artikel-linux-monitoring-tools\Munin-620x396.png
+Released under the terms of GNU General Public License version 2, Zabbix is free software.
-Munin is both a network and a system monitoring tool which offers alerts for when metrics go beyond a given threshold. It uses RRDtool to create the graphs and it has web interface to display these graphs. Its emphasis is on plug and play capabilities with a number of plugins available.
+===== nmon =====
-* http://munin-monitoring.org/
+  * http://nmon.sourceforge.net/pmwiki.php
-* Read More: Install Munin Network Monitoring Tool in Linux
+  * http://nmon.sourceforge.net/pmwiki.php?n=Site.Documentation
+nmon (short hand for Nigel's Monitor) is a computer performance system monitor tool for the AIX and Linux operating systems. The nmon tool has two modes a) displays the performance stats on-screen in a condensed format or b) the same stats are saved to a comma-separated values (CSV) data file for later graphing and analysis to aid the understanding of computer resource use, tuning options and bottlenecks. nmon for Linux is open source and available under GNU General Public License while the nmon for AIX is a proprietary software integrated into AIX.
-Nagios – Network/Server Monitoring
+===== conky =====
+  * https://github.com/brndnmtthws/conky
+  * https://github.com/brndnmtthws/conky/wiki
+Conky is a free software desktop system monitor for the X Window System. It is available for Linux, FreeBSD, and OpenBSD. Conky is highly configurable and is able to monitor many system variables including the status of the CPU, memory, swap space, disk storage, temperatures, processes, network interfaces, battery power, system messages, e-mail inboxes, Arch Linux updates, many popular music players (MPD, XMMS2, BMPx, Audacious, etc.), weather updates, breaking news, and much more. Unlike system monitors that use high-level widget toolkits to render their information, Conky is drawn directly in an X window. This allows it to be configured such that it consumes relatively few system resources.
-Nagios is an leading open source powerful monitoring system that enables network/system administrators to identify and resolve server related problems before they affect major business processes. With the Nagios system, administrators can able to monitor remote Linux, Windows, Switches, Routers and Printers on a single window. It shows critical warnings and indicates if something went wrong in your network/server which indirectly helps you to begin remediation processes before they occur.
+Conky was hailed as "one of the best maintained, and definitely one of the most useful, programs in the world of open source" in Linux Magazine.
-~\ownCloud\zim\Bilder\DEF\artikel-linux-monitoring-tools\nagios.jpg
+It comes pre-configured in the default installation of Pinguy OS and CrunchBang Linux.
-Nagios is system and network monitoring tool that helps you monitor monitor your many servers. It has support for alerting for when things go wrong. It also has many plugins written for the platform.
+===== Glances =====
-* http://www.nagios.org/
+  * https://nicolargo.github.io/glances/
-* Read More : Install Nagios Monitoring System to Monitor Remote Linux/Windows Hosts
+  * https://github.com/nicolargo/glances/wiki
+Glances is a cross-platform monitoring tool which aims to present a large amount of monitoring information through a curses or Web based interface. The information dynamically adapts depending on the size of the user interface. It can also work in client/server mode. Remote monitoring could be done via terminal, Web interface or API (XML-RPC and RESTful). Stats can also be exported to files or external time/value databases. Glances is written in Python and uses libraries to grab information from your system. It is based on an open architecture where developers can add new plugins or exports modules.
+===== sarg =====
+  * https://sourceforge.net/projects/sarg/
+  * https://linux.die.net/man/1/sarg
+sarg - Squid Analysis Report Generator is a tool that allow you to view "where" your users are going to on the Internet. sarg generate HTML reports, with informations about users, IP Addresses, bytes, sites and times. These HTML files can appear in your web server's directory for browsing by users or administrators. You may also have sarg email the reports to the Squid Cache administrator.
-Icinga – Next Generation Server Monitoring
+sarg is a logfile parser and anylizer for the Squid Web Proxy Cache, which can be found at http://www.squid-cache.org/. More information is available at http://sarg.sourceforge.net/.
+sarg can take the squid access log as its input, or optionally the squidGuard http://www.squidguard.org/ Squid filter/redirector logfile format.
-Unlike the other tools, Icinga is a network monitoring program, it shows you many options and information about your network connections, devices and processes, it’s a very good choice for those who are looking for a good tool to monitor their networking stuffs.
+===== libstatgrab / saidar =====
-Icinga Monitoring ToolIcinga Monitoring Tool
+  * https://libstatgrab.org/
+  * https://libstatgrab.org/#documentation
+  * https://github.com/libstatgrab/libstatgrab
+libstatgrab is a library that provides cross platform access to statistics about the system on which it’s run. It’s written in C and presents a selection of useful interfaces which can be used to access key system statistics. The current list of statistics includes CPU usage, memory utilisation, disk usage, process counts, network traffic, disk I/O, and more.
-~\ownCloud\zim\Bilder\DEF\artikel-linux-monitoring-tools\Icinga.jpeg
+The current list of supported and tested platforms includes FreeBSD, Linux, NetBSD, OpenBSD, Solaris, DragonFly BSD, HP-UX and AIX. We are always happy to accept patches to extend support to other operating systems.
-Features of Icinga
+The package also includes a couple of useful tools. The first, saidar, provides a curses-based interface to viewing the current state of the system. The second, statgrab, gives a sysctl-style interface to the statistics gathered by libstatgrab. This extends the use of libstatgrab to people writing scripts or anything else that can’t easily make C function calls. Included with statgrab is a script to generate an MRTG configuration file to use statgrab.
-* Icinga is also free and open-source.
-* Very functional in monitoring everything you may have in networking.
-* Support for MySQL and PostgreSQL is included.
-* Real-time monitoring with A nice web interface.
-* Very expendable with modules and extensions.
-* Icinga supports applying services and actions to hosts.
-* A lot more to discover..
-* Read More: Install Icinga in RHEL/CentOS 7/6
+The library part of libstatgrab is licensed under the GNU LGPL, but the tools and examples are licensed under the GNU GPL.
+===== RRDtool =====
+  * https://oss.oetiker.ch/rrdtool/
+  * https://oss.oetiker.ch/rrdtool/doc/index.en.html
+RRDtool is the OpenSource industry standard, high performance data logging and graphing system for time series data. RRDtool can be easily integrated in shell scripts, perl, python, ruby, lua or tcl applications.
-Zenoss
+===== monit / M/Monit =====
+  * https://mmonit.com/monit/
+  * https://mmonit.com/
+  * https://bitbucket.org/tildeslash/monit/src/master/
+  * https://mmonit.com/monit/documentation/monit.html
+Monit is a free, open-source process supervision tool for Unix and Linux. With Monit, system status can be viewed directly from the command line, or via the native HTTP(S) web server. Monit is able to do automatic maintenance, repair, and run meaningful causal actions in error situations.[3] Monit rose to popularity with Ruby on Rails and the Mongrel web server, because a tool was needed that could manage the many identical Mongrel processes that needed to be run to support a scalable Ruby on Rails site, and Monit was fairly uniquely suited for the needs of the Ruby on Rails community. Many popular Rails sites have used Monit, including Twitter and scribd.
-~\ownCloud\zim\Bilder\DEF\artikel-linux-monitoring-tools\zenoss.jpg
+Monit can restart a process automatically if process dies or monitor process characteristics, such as memory or cpu cycles and alert by email or execute and action.
-Zenoss provides a web interface that allows you to monitor all system and network metrics. Moreover it discovers network resources and changes in network configurations. It has alerts for you to take action on and it supports the Nagios plugins.
+Additionally M/Monit can monitor and manage distributed computer systems, M/Monit uses Monit as an agent and can manage and monitor. M/Monit is licensed software.
-* http://www.zenoss.com/
+===== Linux process explorer =====
+  * https://github.com/wolfc01/procexp/blob/master/README.md
+Graphical process explorer for Linux. Shows process information: process tree, TCP IP connections and graphical performance figures for processes. Aims to mimic Windows procexp from sysinternals, and aims to be more usable than top and ps, especially for advanced users.
-Cacti
+===== df =====
+  * https://en.wikipedia.org/wiki/Df_(Unix)
+  * https://pubs.opengroup.org/onlinepubs/9699919799/utilities/df.html
+df (abbreviation for disk free) is a standard Unix command used to display the amount of available disk space for file systems on which the invoking user has appropriate read access. df is typically implemented using the statfs or statvfs system calls.
-Cacti is nothing more than a free & open-source web interface for RRDtool, it is used often to monitor the bandwidth using SNMP (Simple Network Management Protocol), it can be used also to monitor CPU usage.
+===== discus =====
+  * https://manpages.ubuntu.com/manpages/bionic/man1/discus.1.html
+discus  aims  to  make  df prettier.  Features  include  color,  bar graphs, and smart formatting of numbers (automatically choosing  the  most  suitable  size  from  kilobytes, megabytes, gigabytes, or terabytes). Or choose your own size, along with specifying the number of decimal places you'd like to see. You may also copy /etc/discusrc to $HOME/.discusrc and customize things to your preference.
-~\ownCloud\zim\Bilder\DEF\artikel-linux-monitoring-tools\cacti.jpg
+===== dstat =====
+  * https://linux.die.net/man/1/dstat
+  * http://dag.wiee.rs/home-made/dstat/
+dstat - versatile tool for generating system resource statistics. Dstat is a versatile replacement for vmstat, iostat and ifstat. Dstat overcomes some of the limitations and adds some extra features. Dstat allows you to view all of your system resources instantly, you can eg. compare disk usage in combination with interrupts from your IDE controller, or compare the network bandwidth numbers directly with the disk throughput (in the same interval). Dstat also cleverly gives you the most detailed information in columns and clearly indicates in what magnitude and unit the output is displayed. Less confusion, less mistakes, more efficient.
-~\ownCloud\zim\Bilder\DEF\artikel-linux-monitoring-tools\Cacti2.png
+Dstat is unique in letting you aggregate block device throughput for a certain diskset or network bandwidth for a group of interfaces, ie. you can see the throughput for all the block devices that make up a single filesystem or storage system.
-(And one for luck!) Cacti is network graphing solution that uses the RRDtool data storage. It allows a user to poll services at predetermined intervals and graph the result. Cacti can be extended to monitor a source of your choice through shell scripts.
+Dstat allows its data to be directly written to a CSV file to be imported and used by OpenOffice, Gnumeric or Excel to create graphs.
-* http://www.cacti.net/
-Features of Cacti
+===== Net-SNMP =====
-* Free & open-source, released under GPL license.
+  * http://www.net-snmp.org/
-* Written in PHP with PL/SQL.
+  * http://www.net-snmp.org/docs/man/
-* A cross-platform tool, it works on Windows and Linux.
+Simple Network Management Protocol (SNMP) is a widely used protocol for monitoring the health and welfare of network equipment (eg. routers), computer equipment and even devices like UPSs. Net-SNMP is a suite of applications used to implement SNMP v1, SNMP v2c and SNMP v3 using both IPv4 and IPv6. The suite includes command-line applications to:
-* User management; you may create different users accounts for Cacti.
+  * retrieve information from an SNMP-capable device, either using single requests (snmpget, snmpgetnext), or multiple requests (snmpwalk, snmptable, snmpdelta).
+  * manipulate configuration information on an SNMP-capable device (snmpset).
+  * retrieve a fixed collection of information from an SNMP-capable device (snmpdf, snmpnetstat, snmpstatus).
+  * convert between numerical and textual forms of MIB OIDs, and display MIB content and structure (snmptranslate).
+  * A graphical MIB browser (tkmib), using Tk/perl.
+  * A daemon application for receiving SNMP notifications (snmptrapd). Selected notifications can be logged (to syslog, the NT Event Log, or a plain text file), forwarded to another SNMP management system, or passed to an external application.
+  * An extensible agent for responding to SNMP queries for management information (snmpd). This includes built-in support for a wide range of MIB information modules, and can be extended using dynamically loaded modules, external scripts and commands, and both the SNMP multiplexing (SMUX) and Agent Extensibility (AgentX) protocols.
+  * A library for developing new SNMP applications, with both C and perl APIs.
-Read More: Install Cacti Network and System Monitoring Tool in Linux
+Net-SNMP is available for many Unix and Unix-like operating systems and also for Microsoft Windows. Note: Functionality can vary depending on the operating system. Please see the README files for information specific to your platform.
+===== incron =====
+  * https://github.com/ar-/incron
+  * http://inotify.aiken.cz/?section=incron&page=about&lang=en
+This program is the "inotify cron" system. It consist of a daemon and a table manipulator. You can use it a similar way as the regular cron. The difference is that the inotify cron handles filesystem events rather than time periods.
-Zabbix
+This project was kicked off by Lukas Jelinek in 2006 and then unfortunatally abandoned in 2012. Upstream development and bug-tracking/fixing continued in 2014 on GitHub: https://github.com/ar-/incron .
-~\ownCloud\zim\Bilder\DEF\artikel-linux-monitoring-tools\zabbix-monitoring.png
+ inotify is an inode-based filesystem notification technology. It provides possibility to simply monitor various events on files in filesystems. It is a very much powerful replacement of (obsolete) dnotify. inotify brings a comfortable way how to manage files used in your applications.
-Zabbix is an open source infrastructure monitoring solution. It can use most databases out there to store the monitoring statistics. The Core is written in C and has a frontend in PHP. If you don’t like installing an agent, Zabbix might be an option for you.
+inotify can be used for such tasks:
-* http://www.zabbix.com/
+  * detecting changes in files and directories (e.g. configuration files, mail directories)
+  * guarding critical files and their eventual automatic recovery
+  * file usage statistics and similar purposes
+  * automatic upload handling
+  * monitoring installations outside of packaging systems
+  * automatic on-change backup and/or versioning
+  * reflecting changes to search databases
+There is much more that can be done using inotify. Switch your fantasy on and incorporate inotify to your application the best way.
-nmon - Monitor Linux Performance
+===== monitorix =====
+  * https://github.com/mikaku/Monitorix
+  * https://www.monitorix.org/
+  * https://www.monitorix.org/documentation.html
+  * https://wiki.archlinux.org/title/monitorix
+Monitorix is a free, open source, lightweight system monitoring tool designed to monitor as many services and system resources as possible. It has been created to be used under production Linux/UNIX servers, but due to its simplicity and small size can be used on embedded devices as well.
-Nmon (stands for Nigel’s performance Monitor) tool, which is used to monitor all Linux resources such as CPU, Memory, Disk Usage, Network, Top processes, NFS, Kernel and much more. This tool comes in two modes: Online Mode and Capture Mode.
+It consists mainly of two programs: a collector, called monitorix, which is a Perl daemon that is started automatically like any other system service, and a CGI script called monitorix.cgi. Monitorix includes its own HTTP server built in (which is listening by default on port 8080/TCP) to see the statistics graphs, so you aren't forced to install a third-party web server to use it. Just point your browser at http://localhost:8080/monitorix.
-The Online Mode, is used for real-time monitoring and Capture Mode, is used to store the output in CSV format for later processing.
+All of its development was initially created for monitoring Red Hat, Fedora and CentOS Linux systems, so this project was made keeping in mind these type of distributions. Today it runs on different GNU/Linux distributions and even in other UNIX systems like FreeBSD, OpenBSD and NetBSD.
-~\ownCloud\zim\Bilder\DEF\artikel-linux-monitoring-tools\nmon.jpg
+It is currently in active development adding new features, new graphs and correcting bugs in the attempt to offer a great tool for daily systems administration.
-~\ownCloud\zim\Bilder\DEF\artikel-linux-monitoring-tools\Nmon-620x383.jpeg
+===== vmstat =====
+  * https://linux.die.net/man/8/vmstat
+  * https://en.wikipedia.org/wiki/Vmstat
+vmstat (virtual memory statistics) is a computer system monitoring tool that collects and displays summary information about operating system memory, processes, interrupts, paging and block I/O. Users of vmstat can specify a sampling interval which permits observing system activity in near-real time.
-nmon either outputs the data on screen or saves it in a comma separated file. You can display CPU, memory, network, filesystems, top processes. The data can also be added to a RRD database for further analysis.
+The vmstat tool is available on most Unix and Unix-like operating systems, such as FreeBSD, Linux or Solaris.
-* http://nmon.sourceforge.net/pmwiki.php
-* Read More: Install Nmon (Performance Monitoring) Tool in Linux
+===== Web VMStat =====
+  * https://github.com/joewalnes/web-vmstats
+Display live Linux system stats (memory, CPU, IO, etc) in a pretty web-page, with charts and everything.
-conky
+===== uptime =====
+  * https://man7.org/linux/man-pages/man1/uptime.1.html
+  * https://en.wikipedia.org/wiki/Uptime#Using_uptime
+uptime gives a one line display of the following information. The current time, how long the system has been running, how many users are currently logged on, and the system load averages for the past 1, 5, and 15 minutes.
-~\ownCloud\zim\Bilder\DEF\artikel-linux-monitoring-tools\conky.jpg
+===== mpstat =====
+  * https://linux.die.net/man/1/mpstat
+  * http://sebastien.godard.pagesperso-orange.fr/
+mpstat - Report processors related statistics. The mpstat command writes to standard output activities for each available processor, processor 0 being the first one. Global average activities among all processors are also reported. The mpstat command can be used both on SMP and UP machines, but in the latter, only global average activities will be printed. If no activity has been selected, then the default report is the CPU utilization report.
-Conky monitors a plethora of different OS stats. It has support for IMAP and POP3 and even support for many popular music players! For the handy person you could extend it with your own scripts or programs using Lua.
+The interval parameter specifies the amount of time in seconds between each report. A value of 0 (or no parameters at all) indicates that processors statistics are to be reported for the time since system startup (boot). The count parameter can be specified in conjunction with the interval parameter if this one is not set to zero. The value of count determines the number of reports generated at interval seconds apart. If the interval parameter is specified without the count parameter, the mpstat command generates reports continuously.
-* http://conky.sourceforge.net/
+===== pmap =====
+  * https://linux.die.net/man/1/pmap
+pmap - report memory map of a process. The pmap command reports the memory map of a process or processes.
-Glances
+===== ps =====
+  * https://man7.org/linux/man-pages/man1/ps.1.html
+  * https://en.wikipedia.org/wiki/Ps_(Unix)
+ps displays information about a selection of the active processes. If you want a repetitive update of the selection and the displayed information, use top instead. In most Unix and Unix-like operating systems, the ps program (short for "process status") displays the currently-running processes. A related Unix utility named top provides a real-time view of the running processes.
-Glances is a monitoring tool built to present as much information as possible in any terminal size, it automatically takes the terminal window size it runs on, in other words, it’s a responsive monitoring tool.
+===== sar =====
+  * https://linux.die.net/man/1/sar
+  * http://sebastien.godard.pagesperso-orange.fr/
+  * http://sebastien.godard.pagesperso-orange.fr/man_sar.html
+sar - Collect, report, or save system activity information. The sar command writes to standard output the contents of selected cumulative activity counters in the operating system. The accounting system, based on the values in the count and interval parameters, writes information the specified number of times spaced at the specified intervals in seconds. If the interval parameter is set to zero, the sar command displays the average statistics for the time since the system was started. If the interval parameter is specified without the count parameter, then reports are generated continuously. The collected data can also be saved in the file specified by the -o filename flag, in addition to being displayed onto the screen. If filename is omitted, sar uses the standard system activity daily data file, the /var/log/sa/sadd file, where the dd parameter indicates the current day. By default all the data available from the kernel are saved in the data file.
-~\ownCloud\zim\Bilder\DEF\artikel-linux-monitoring-tools\glances.jpg
+===== Sysstat =====
+  * http://sebastien.godard.pagesperso-orange.fr/
+The sysstat utilities are a collection of performance monitoring tools for Linux. These include sar, sadf, mpstat, iostat, tapestat, pidstat, cifsiostat  and sa tools. Go to the Features page to display a list of sysstat's features, or see the Documentation page to learn some more about them.
+Sysstat is Open Source / Free Software, and is freely available under the GNU General Public License, version 2.
-~\ownCloud\zim\Bilder\DEF\artikel-linux-monitoring-tools\Glances2.jpeg
+Sysstat's main features:
-Glances monitors your system and aims to present a maximum amount of information in a minimum amount of space. It has the capability to function in a client/server mode as well as monitoring remotely. It also has a web interface.
+  * Includes four groups of monitoring tools (sar / sadc / sadf, iostat / tapestat / cifsiostat, mpstat, pidstat) for global system performance analysis.
-* https://github.com/nicolargo/glances
+  * Can monitor a huge number of different metrics:
-* Install Glances on RHEL/CentOS/Fedora and Ubuntu/Debian
+    * Input / Output and transfer rate statistics (global, per device, per partition, per network filesystem and per Linux task / PID).
+    * CPU statistics (global, per CPU, per NUMA nodes and per Linux task / PID), including support for virtualization architectures.
-Features
+    * Memory, hugepages and swap space utilization statistics.
-* Licensed under LGPL and written in Python.
+    * Virtual memory, paging and fault statistics.
-* Cross-platform, it works on Windows, Mac, BSD and Linux.
+    * Per-task (per-PID) memory and page fault statistics.
-* Available in most Linux official repositories.
+    * Global CPU and page fault statistics for tasks and all their children.
-* A It gives a lot of information about your system.
+    * Process creation activity.
-* Built using curses.
+    * Interrupt statistics (global, per CPU and per interrupt, including potential APIC interrupt sources, hardware and software interrupts).
+    * Extensive network statistics: network interface activity (number of packets and kB received and transmitted per second, etc.) including failures from network devices; network traffic statistics for IP, TCP, ICMP and UDP protocols based on SNMPv2 standards; support for IPv6-related protocols.
+    * Fibre Channel traffic statistics.
-Sarg – Squid Bandwidth Monitoring
+    * Software-based network processing (softnet) statistics.
+    * NFS server and client activity.
-Sarg (Squid Analysis Report Generator) is a free & open-source tool which act as a monitoring tool for your Squid proxy server, it creates reports about your Squid proxy server users, IP addresses, the sites they visit beside some other information.
+    * Sockets statistics.
-Monitor Squid Proxy LogsMonitor Squid Proxy Logs
+    * Run queue and system load statistics.
+    * Kernel internal tables utilization statistics.
-~\ownCloud\zim\Bilder\DEF\artikel-linux-monitoring-tools\Sarg.jpeg
+    * System and per Linux task switching activity.
+    * Swapping statistics.
-Features of Sarg
+    * TTY devices activity.
-* Licensed under GPL 2 and available in many languages.
+    * Power management statistics (instantaneous and average CPU clock frequency, fans speed, devices temperature, voltage inputs)
-* Works under Linux & FreeBSD.
+    * USB devices plugged into the system.
-* Generates report in HTML format.
+    * Filesystems utilization (inodes and blocks).
-* Very easy to install & use.
+    * Tape drives statistics.
+    * Pressure-Stall Information statistics.
-Read More: Install Sarg “Squid Bandwidth Monitoring” Tool in Linux
+  * Can generate graphs (SVG format - Scalable Vector Graphics) that can be displayed in your favorite web browser!
+  * Most system statistics can be saved in a file for future inspection.
+  * Allows to configure the length of data history to keep.
-saidar
+  * On the fly detection of new devices (disks, network interfaces, etc.) that are created or registered dynamically.
+  * Support for UP and SMP machines, including machines with hyperthreaded or multi-core processors.
-~\ownCloud\zim\Bilder\DEF\artikel-linux-monitoring-tools\saidar.jpg
+  * Support for hotplug CPUs (it detects automagically processors that are disabled or enabled on the fly) and tickless CPUs.
+  * Works on many different architectures, whether 32- or 64-bit.
-Saidar is a very small tool that gives you basic information about your system resources. It displays a full screen of the standard system resources. The emphasis for saidar is being as simple as possible.
+  * Needs very little CPU time to run (written in C).
-* https://packages.debian.org/sid/utils/saidar
+  * System statistics collected by sar/sadc can be exported in various different formats (CSV, XML, JSON, SVG, etc.). DTD and XML Schema documents are included in sysstat package. JSON output format is also available for mpstat and iostat commands.
+  * sar data can also be exported by sadf to PCP (Performance Co-Pilot) archive.
+  * Smart color output for easier statistics reading.
+  * Internationalization support (sysstat has been translated into numerous different languages). Sysstat is now part of the Translation Project.
-RRDtool
+  * Sysstat commands can automatically select the unit used to display sizes for easier reading (see option --human).
+  * Many programs available on the internet to use sysstat's data to make graphs (one of them, isag, is included in sysstat).
-~\ownCloud\zim\Bilder\DEF\artikel-linux-monitoring-tools\rrdtool.jpg
+  * iostat has support for devices managed by drivers in userspace like spdk.
-RRDtool is a tool developed to handle round-robin databases or RRD. RRD aims to handle time-series data like CPU load, temperatures etc. This tool provides a way to extract RRD data in a graphical format.
-* http://oss.oetiker.ch/rrdtool/
-monit
-Monit is a free open source and web based process supervision utility that automatically monitors and managers system processes, programs, files, directories, permissions, checksums and filesystems.
-It monitors services like Apache, MySQL, Mail, FTP, ProFTP, Nginx, SSH and so on. The system status can be viewed from the command line or using it own web interface.
-Monit is a nice program that monitors your Linux & Unix server, it can monitor everything you have on your server, from the main server (Apache, Nginx..) to files permissions, files hashes and web services. Plus a lot of things.
-~\ownCloud\zim\Bilder\DEF\artikel-linux-monitoring-tools\monit.jpg
-Monit has the capability of sending you alerts as well as restarting services if they run into trouble. It’s possible to perform any type of check you could write a script for with monit and it has a web user interface to ease your eyes.
-* http://mmonit.com/monit
-* Read More: Install Monit Tool in RHEL/CentOS/Fedora and Ubuntu/Debian
-* Read More : Linux Process Monitoring with Monit
-Features of Monit
-* Free & open-source, released under AGPL and written in C.
-* It can be started from the command line interface or via its special web interface.
-* Very effective in monitoring all the software on your system and services.
-* A nice web interface with beautiful charts for CPU and RAM usage.
-* Monit can automatically take actions in emergency situations.
-* A lot more..
-Linux process explorer
-~\ownCloud\zim\Bilder\DEF\artikel-linux-monitoring-tools\linux-process-monitor.jpg
-Linux process explorer is akin to the activity monitor for OSX or the windows equivalent. It aims to be more usable than top or ps. You can view each process and see how much memory usage or CPU it uses.
-* http://sourceforge.net/projects/procexp/
-df
-~\ownCloud\zim\Bilder\DEF\artikel-linux-monitoring-tools\df.jpg
-df is an abbreviation for disk free and is pre-installed program in all unix systems used to display the amount of available disk space for filesystems which the user have access to.
-discus
-~\ownCloud\zim\Bilder\DEF\artikel-linux-monitoring-tools\discus.jpg
-Discus is similar to df however it aims to improve df by making it prettier using fancy features as colors, graphs and smart formatting of numbers.
-* http://packages.ubuntu.com/lucid/utils/discus
-Apache Status Monitoring
-Apache Module mod_status is an Apache server module that allows you to monitor the workers status of the Apache server. It generates a report in an easy to read HTML format. It shows you the status of all the workers, how much CPU each one using, and what requests are currently handled and number of working and not working workers.
-~\ownCloud\zim\Bilder\DEF\artikel-linux-monitoring-tools\Apache-Monitoring.jpeg
-Read More: Apache Web Server Load and Page Statistics Monitoring
-xosview
-~\ownCloud\zim\Bilder\DEF\artikel-linux-monitoring-tools\xosview.jpg
-xosview is a classic system monitoring tool and it gives you a simple overview of all the different parts of the including IRQ.
-* http://www.pogo.org.uk/~mark/xosview/
-Dstat
-~\ownCloud\zim\Bilder\DEF\artikel-linux-monitoring-tools\dstat.jpg
-Dstat aims to be a replacement for vmstat, iostat, netstat and ifstat. It allows you to view all of your system resources in real-time. The data can then be exported into csv. Most importantly dstat allows for plugins and could thus be extended into areas not yet known to mankind.
-* http://dag.wiee.rs/home-made/dstat/
-Net-SNMP
-SNMP is the protocol ‘simple network management protocol’ and the Net-SNMP tool suite helps you collect accurate information about your servers using this protocol.
-* http://www.net-snmp.org/
-incron
-Incron allows you to monitor a directory tree and then take action on those changes. If you wanted to copy files to directory ‘b’ once new files appeared in directory ‘a’ that’s exactly what incron does.
-* http://inotify.aiken.cz/?section=incron&page=about&lang=en
-monitorix – System and Network Monitoring
-Monitorix is a free lightweight utility that is designed to run and monitor system and network resources as many as possible in Linux/Unix servers. It has a built in HTTP web server that regularly collects system and network information and display them in graphs. It Monitors system load average and usage, memory allocation, disk driver health, system services, network ports, mail statistics (Sendmail, Postfix, Dovecot, etc), MySQL statistics and many more. It designed to monitor overall system performance and helps in detecting failures, bottlenecks, abnormal activities etc.
-~\ownCloud\zim\Bilder\DEF\artikel-linux-monitoring-tools\Monitorix-Monitoring-592x450.png
-Monitorix is lightweight system monitoring tool. It helps you monitor a single machine and gives you a wealth of metrics. It also has a built-in HTTP server to view graphs and a reporting mechanism of all metrics.
-* http://www.monitorix.org/
-* Read More : Monitorix a System and Network Monitoring Tool for Linux
-vmstat
-Linux VmStat command used to display statistics of virtual memory, kernerl threads, disks, system processes, I/O blocks, interrupts, CPU activity and much more. By default vmstat command is not available under Linux systems you need to install a package called sysstat that includes a vmstat program. The common usage of command format is.
-procs -----------memory---------- ---swap-- -----io---- -system-- ------cpu-----
- r  b   swpd   free   buff  cache   si   so    bi    bo   in   cs us sy id wa st
-  0      0 444512  17068 281888    0    0     1     2   27   24  1  0 99  0  0
-vmstat or virtual memory statistics is a small built-in tool that monitors and displays a summary about the memory in the machine.
-For more Vmstat examples read : 6 Vmstat Command Examples in Linux
-Web VMStat – System Statistics Monitoring
-Web VMStat is a very simple web application programmer, that provides a real time system information usage, from CPU to RAM, Swap and input/output information in html format.
-~\ownCloud\zim\Bilder\DEF\artikel-linux-monitoring-tools\Web-VMStat.png
-Read More: Web VMStat: A Real Time System Statistics Tool for Linux
-uptime
-This small command that quickly gives you information about how long the machine has been running, how many users currently are logged on and the system load average for the past 1, 5 and 15 minutes.
-mpstat
-~\ownCloud\zim\Bilder\DEF\artikel-linux-monitoring-tools\mpstat.jpg
-mpstat is a built-in tool that monitors cpu usage. The most common command is using mpstat -P ALL which gives you the usage of all the cores. You can also get an interval update of the CPU usage.
-pmap
-~\ownCloud\zim\Bilder\DEF\artikel-linux-monitoring-tools\pmap.jpg
-pmap is a built-in tool that reports the memory map of a process. You can use this command to find out causes of memory bottlenecks.
-ps
-~\ownCloud\zim\Bilder\DEF\artikel-linux-monitoring-tools\ps.jpg
-The ps command will give you an overview of all the current processes. You can easily select all processes using the command ps -A
-sar
-~\ownCloud\zim\Bilder\DEF\artikel-linux-monitoring-tools\sar.jpg
-sar is a part of the sysstat package and helps you to collect, report and save different system metrics. With different commands it will give you CPU, memory and I/O usage among other things.
-* http://sebastien.godard.pagesperso-orange.fr/
-Sysstat – All-in-One System Performance Monitoring
-Another monitoring tool for your Linux system. Sysstat is not a real command in fact, it’s just the name of the project, Sysstat in fact is a package that includes many performance monitoring tools like iostat, sadf, pidstat beside many other tools which shows you many statistics about your Linux OS.
-~\ownCloud\zim\Bilder\DEF\artikel-linux-monitoring-tools\Sysstat-620x381.png
-Features of Sysstat
-* Available in many Linux distributions repositories by default.
-* Ability to create statistics about RAM, CPU, SWAP usage. Beside the ability to monitor Linux kernel activity, NFS server, Sockets, TTY and filesystems.
-* Ability to monitor input & output statistics for devices, tasks.. etc.
-* Ability to output reports about network interfaces and devices, with support for IPv6.
-* Sysstat can show you the power statistics (usage, devices, the fans speed.. etc) as well.
-* Many other features..
-Read More: Install Sysstat in Linux and 20 Useful Commands of Sysstat
-collectl- All-in-One Performance Monitoring Tool
-Collectl is a yet another powerful and feature rich command line based utility, that can be used to gather information about Linux system resources such as CPU usage, memory, network, inodes, processes, nfs, tcp, sockets and much more.
-~\ownCloud\zim\Bilder\DEF\artikel-linux-monitoring-tools\collectl.jpg
-~\ownCloud\zim\Bilder\DEF\artikel-linux-monitoring-tools\Collectl-620x410.jpg
-Similar to sar collectl collects performance metrics for your machine. By default it shows cpu, network and disk stats but it collects a lot more. The difference to sar is collectl is able to deal with times below 1 second, it can be fed into a plotting tool directly and collectl monitors processes more extensively.
-* http://collectl.sourceforge.net/
-* Read More: Install Collectl (All-in-One Performance Monitoring) Tool in Linux
-iostat
-~\ownCloud\zim\Bilder\DEF\artikel-linux-monitoring-tools\iostat.jpg
+===== iostat =====
+  * http://sebastien.godard.pagesperso-orange.fr/
+  * http://sebastien.godard.pagesperso-orange.fr/man_iostat.html
 iostat is also part of the sysstat package. This command is used for monitoring system input/output. The reports themselves can be used to change system configurations to better balance input/output load between hard drives in your machine.
-* http://sebastien.godard.pagesperso-orange.fr/
-free
-~\ownCloud\zim\Bilder\DEF\artikel-linux-monitoring-tools\free.jpg
-This is a built-in command that displays the total amount of free and used physical memory on your machine. It also displays the buffers used by the kernel at that given moment.
-/Proc file system
-~\ownCloud\zim\Bilder\DEF\artikel-linux-monitoring-tools\procfile.jpg
-The proc file system gives you a peek into kernel statistics. From these statistics you can get detailed information about the different hardware devices on your machine. Take a look at the full list of the proc file statistics
-GKrellM
-GKrellm is a gui application that monitor the status of your hardware such CPU, main memory, hard disks, network interfaces and many other things. It can also monitor and launch a mail reader of your choice.
-* http://members.dslextreme.com/users/billw/gkrellm/gkrellm.html
-Gnome system monitor
-~\ownCloud\zim\Bilder\DEF\artikel-linux-monitoring-tools\gnome-system-monitor.jpg
-Gnome system monitor is a basic system monitoring tool that has features looking at process dependencies from a tree view, kill or renice processes and graphs of all server metrics.
-* http://freecode.com/projects/gnome-system-monitor
-GoAccess
-~\ownCloud\zim\Bilder\DEF\artikel-linux-monitoring-tools\goaccess.jpg
-GoAccess is a real-time web log analyzer which analyzes the access log from either apache, nginx or amazon cloudfront. It’s also possible to output the data into HTML, JSON or CSV. It will give you general statistics, top visitors, 404s, geolocation and many other things.
-* http://goaccess.io/
-Logwatch
+===== collectl =====
+  * https://linux.die.net/man/1/collectl
+  * http://collectl.sourceforge.net/
+  * http://collectl.sourceforge.net/Documentation.html
+ There are a number of times in which you find yourself needing performance data. These can include benchmarking, monitoring a system's general heath or trying to determine what your system was doing at some time in the past. Sometimes you just want to know what the system is doing right now. Depending on what you're doing, you often end up using different tools, each designed to for that specific situation.
-Logwatch is a log analysis system. It parses through your system’s logs and creates a report analyzing the areas that you specify. It can give you daily reports with short digests of the activities taking place on your machine.
+Unlike most monitoring tools that either focus on a small set of statistics, format their output in only one way, run either interatively or as a daemon but not both, collectl tries to do it all. You can choose to monitor any of a broad set of subsystems which currently include buddyinfo, cpu, disk, inodes, infiniband, lustre, memory, network, nfs, processes, quadrics, slabs, sockets and tcp.
-* http://sourceforge.net/projects/logwatch/
+===== free =====
+  * https://man7.org/linux/man-pages/man1/free.1.html
+free displays the total amount of free and used physical and swap memory in the system, as well as the buffers and caches used by the kernel. The information is gathered by parsing /proc/meminfo.
-Swatch
+===== /proc file system =====
+  * https://www.kernel.org/doc/html/latest/filesystems/proc.html
+  * https://tldp.org/LDP/Linux-Filesystem-Hierarchy/html/proc.html
+/proc is very special in that it is also a virtual filesystem. It's sometimes referred to as a process information pseudo-file system. It doesn't contain 'real' files but runtime system information (e.g. system memory, devices mounted, hardware configuration, etc). For this reason it can be regarded as a control and information centre for the kernel. In fact, quite a lot of system utilities are simply calls to files in this directory. For example, 'lsmod' is the same as 'cat /proc/modules' while 'lspci' is a synonym for 'cat /proc/pci'. By altering files located in this directory you can even read/change kernel parameters (sysctl) while the system is running.
-~\ownCloud\zim\Bilder\DEF\artikel-linux-monitoring-tools\swatch.jpg
+===== GKrellM =====
+  * http://gkrellm.srcbox.net/
+  * https://git.srcbox.net/gkrellm/gkrellm
+GKrellM is a single process stack of system monitors which supports applying themes to match its appearance to your window manager, Gtk, or any other theme.
-Much like Logwatch Swatch also monitors your logs, but instead of giving reports it watches for regular expression and notifies you via mail or the console when there is a match. It could be used for intruder detection for example.
+===== Gnome system monitor =====
-* http://sourceforge.net/projects/swatch/
+  * https://wiki.gnome.org/Apps/SystemMonitor
+  * https://help.gnome.org/users/gnome-system-monitor/stable/
+System Monitor is a tool to manage running processes and monitor system resources.
+===== GoAccess =====
+  * https://github.com/allinurl/goaccess
+  * https://goaccess.io/
+  * https://goaccess.io/man
+GoAccess is an open-source web analytics application for Unix-like operating systems. It has both a text-based and a web application user interface. It can provide real-time analytics by continuously monitoring web server logs. GoAccess is an open source real-time web log analyzer and interactive viewer that runs in a terminal in *nix systems or through your browser.
-MultiTail
+It provides fast and valuable HTTP statistics for system administrators that require a visual server report on the fly.
-~\ownCloud\zim\Bilder\DEF\artikel-linux-monitoring-tools\multitail.jpg
+===== Logwatch =====
+  * https://linux.die.net/man/8/logwatch
+  * https://sourceforge.net/projects/logwatch/
+Logwatch is a customizable, pluggable log-monitoring system. It will go through your logs for a given period of time and make a report in the areas that you wish with the detail that you wish. Logwatch is being used for Linux and many types of UNIX.
-MultiTail helps you monitor logfiles in multiple windows. You can merge two or more of these logfiles into one. It will also use colors to display the logfiles for easier reading with the help of regular expressions.
+===== Swatchdog =====
-* http://www.vanheusden.com/multitail/
+  * http://sourceforge.net/projects/swatch/
+  * http://swatch.sourceforge.net/
+Swatch: the active log file monitoring tool. Swatch started out as the "simple watchdog" for activly monitoring log files produced by UNIX's syslog facility. It has since been evolving into a utility that can monitor just about any type of log.
+===== MultiTail =====
+  * https://github.com/halturin/multitail
+  * http://www.vanheusden.com/multitail/
+  * https://www.vanheusden.com/multitail/examples.html
+  * https://linux.die.net/man/1/multitail
+MultiTail allows you to monitor logfiles and command output in multiple windows in a terminal, colorize, filter, and merge.
 acct or psacct – Monitor User Activity