Nagios

Nagios (formerly Netsaint) is an open source, freely distributed, fast, flexible and very powerful command-line/web-based utility implemented in C and designed from the ground up to be used as a for network services and hosts monitoring solution. It is capable of monitoring any Linux kernel-based OS, BSD distributions, UNIXes, Netware, and Microsoft Windows systems.

Nagios will help you to monitor all the systems on your IT infrastructure, reduce downtime for your company leading to reduced business losses, detect and repair security breaches in time before anything bad happens, get notified instantly when problems arise, detect issues before they occur, share data with stakeholders, as well as to plan and budget for IT upgrades.

Features at a glance

The software is capable of monitoring network services, including SMTP (Simple Mail Transfer Protocol), HTTP (Hypertext Transfer Protocol), POP3 (Post Office Protocol), PING, NNTP (Network News Transfer Protocol), as well as host resources, including processor load, memory and disk usage, log files, and running processes.

The software also features the ability to acknowledge problems, to schedule downtime for suppressing service and host notifications, to define network host hierarchy, and to notify contacts, via email, pager or other methods, when problems arise and are resolved. In addition, it offers support for implementing distributed and redundant monitoring servers.

Another interesting feature is the built-in and powerful plugin architecture, which allows users to extend the default functionality of the product through plugins. At the moment, thousands of plugins exist for the Nagios product and can be easily installed from within the app.

Supported operating systems

At the moment, Nagios runs successfully on a wide range of Linux kernel-based operating systems, independent of a hardware platform (32-bit and 64-bit are supported at this time). It can be easily deployed on any distribution of Linux via their main software repositories.

What is new in this release:

• Improved config file parsing
• Fixed configure script to check for existence of /run for lock file (in regards to CVE-2017-12847)
• Use absolute paths when deleting check results files
• Add sanity checking in reassign_worker

What is new in version 4.2.4:

• Fixed another root privilege escalation (CVE-2016-9566)

What is new in version 4.1.1:

• Fixed CGI's not being able to read object configuration data when dependencies were present (John Frickson)
• Fix for exclude (!) not working for dependencies (John Frickson)

What is new in version 4.0.8 / 4.1.0 RC1:

• ENHANCEMENTS:
• Removed 8 kB string size limitation in JSON CGIs (Eric Stanley)
• Re-implemented auto-rescheduling of checks (Eric Mislivec)
• Avoid bunching of checks delayed due to timeperiod constraints (Eric Stanley)
• Limit the number of autocalculated core workers to not spawn too many on large systems (Eric Mislivec, Janice Singh)
• FIXES:
• Removed quotes from numeric duration values in JSON CGIs (Eric Stanley)
• Fixed escaping in JSON CGIs so all required characters are escaped, and in the correct order (Eric Stanley)
• Fixed segfault in archive JSON CGI when plugin output was empty (Eric Stanley)
• Fixed several possibilities for buffer overflow (Eric Mislivec, Dirkjan Bussink)
• Fixed Tracker #582, #626: Handle VAR=VAL assignments at the start of simple commands (Eric Mislivec, Phil Randal)
• Fixed Tracker #630: Recognize '' as redirection operators (Eric Mislivec)
• Corrected worker communication protocol documentation (Phil Mayers)
• Fixed init script to leave config test log in a better location, let sysconfig override init script variables, and not remove nagios.cmd when attempting to start with another instance running (Eric Mislivec, Robin Kearney)
• Fixed Tracker #361: Downtime notifications not displayed properly (Andrew Widdersheim)

What is new in version 4.0.8:

• ENHANCEMENTS:
• Removed 8 kB string size limitation in JSON CGIs (Eric Stanley)
• Re-implemented auto-rescheduling of checks (Eric Mislivec)
• Avoid bunching of checks delayed due to timeperiod constraints (Eric Stanley)
• Limit the number of autocalculated core workers to not spawn too many on large systems (Eric Mislivec, Janice Singh)
• FIXES:
• Removed quotes from numeric duration values in JSON CGIs (Eric Stanley)
• Fixed escaping in JSON CGIs so all required characters are escaped, and in the correct order (Eric Stanley)
• Fixed segfault in archive JSON CGI when plugin output was empty (Eric Stanley)
• Fixed several possibilities for buffer overflow (Eric Mislivec, Dirkjan Bussink)
• Fixed Tracker #582, #626: Handle VAR=VAL assignments at the start of simple commands (Eric Mislivec, Phil Randal)
• Fixed Tracker #630: Recognize '' as redirection operators (Eric Mislivec)
• Corrected worker communication protocol documentation (Phil Mayers)
• Fixed init script to leave config test log in a better location, let sysconfig override init script variables, and not remove nagios.cmd when attempting to start with another instance running (Eric Mislivec, Robin Kearney)
• Fixed Tracker #361: Downtime notifications not displayed properly (Andrew Widdersheim)

What is new in version 4.0.1:

• ENHANCEMENTS:
• Added compiler flags in RPM spec file to reduce compiler noise (Dan Wittenberg)
• Added logging of failure in dlclose() call (Anton Lofgren)
• Added a simple query handler interface, nagios-qh.rb (Dan Wittenberg)
• Multiple code simplifications, additional error handling in downtime code (Andreas Ericsson)
• FIXES:
• Reverted commit f99a9a7b which set check_interval to 1 if it was configured as zero.
• Corrected order of arguments when logging unknown hosts/services (Scott Wilkerson)
• Downtime initialized before retention data read (Eric Stanley)
• Patches to make RPM build again (Dan Wittenberg)
• Ensure that scheduled_downtime_depth never drops below zero (Andreas Ericsson)

What is new in version 3.4.0:

• ENHANCEMENTS:
• Use execv() to execute active check commands (#86 - Ton Voon, dnsmichi)
• Added service_check_timeout_state configuration variable (Bill McGonigle)
• Permanently remove sleep on run_event == FALSE in main loop (Max - perldork at webwizarddesign.com)
• Reduce notification load by moving notification viability check into notification list creation (Opsview Team)
• Added code to apply allow_empty_hostgroup_assignment flag to host and service dependencies (Daniel Wittenberg)
• Users can now see hostgroups and servicegroups that contain at least one host or service they are authorized for, instead of having to be authorized for them all (Ethan Galstad)
• RSS feed boxes fallback if an error occurs (Ethan Galstad)
• RSS feeds no longer block main page load (Mike Guthrie)
• FIXES:
• Fix $NOTIFICATIONRECIPIENTS$ macro to contain all contacts assigned to host|service, not only notified contacts (Bug #98 Matt Harrington)
• Scheduled Downtime Notifications Resent On Nagios Restart/reload (Bug #124 - ricardo)
• NOTIFICATIONTYPE MACRO never became CUSTOM (Bug #168 - Alexey Dvoryanchikov)
• Plugged minor memory leaks in notification logic

What is new in version 3.2.0:

• Several bugfixes, including service check scheduling and daylight savings times reporting.

What is new in version 3.1.0:

• A new feature was added to check for new Nagios releases.
• Several bugs were fixed with event handler logging, embedded perl, CPU hogging issues under OpenBSD, timeperiod calculation routines, scheduling checks from the Web interface, and the handling of problem states after Nagios restarted.

What is new in version 3.0.6:

• Security fixes related to CGI submission of external commands and processing of adaptive data commands.
• x509 certificate authentication support and wildcard host matching in CGIs were added.
• Minor improvements were made to the RPM spec file, out-of-disk-space error handling, and system command timeout handling.

What is new in version 3.0.5:

• A security fix was made for Cross Site Request Forgery (CSRF).
• New documentation on CGI security recommendations was written.
• Fixes were made for AIX compiler warnings, sample configuration file variables, the RPM spec file, and a multiline continuation bug.

What is new in version 3.0.4:

• Fixes for segfaults under Solaris, high CPU utilization under OS X, encoded variable problems in CGIs, and sample event handlers.