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Nagios Core

Nagios Core


What is Nagios Core?

Nagios provides monitoring of all mission-critical infrastructure components. Multiple APIs and community-build add-ons enable integration and monitoring with in-house and third-party applications for optimized scaling.

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Recent Reviews

TrustRadius Insights

Nagios, a popular IT infrastructure monitoring tool, has proven to be a valuable asset for organizations across various departments. With …
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Nagios for the win

6 out of 10
May 17, 2021
We use Nagios as our alternative Network Monitoring Software for our data centers and out branches. It helps you monitor branch with down …
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Product Demos

nagios core


Nagios Exploit DEMO - Remote CodeExec CVE-2016-9565 & Root PrivEsc CVE-2016-9566

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Product Details

What is Nagios Core?

Nagios provides monitoring of all mission-critical infrastructure components including applications, services, operating systems, network protocols, systems metrics, and network infrastructure. Multiple APIs provide for simple integration with in-house and third-party applications. Thousands of community-developed add-ons extend monitoring and native alerting functionality. Third-party add-ons are available for monitoring in-house applications, services, and systems.

The vendor says Nagios is the industry standard In IT Infrastructure Monitoring. The vendor says the powerful Nagios Core 4 monitoring engine provides a high level of performance, and that its high-efficiency worker processes allow for scalability and monitoring effectiveness. It is designed to provide a central view of a company's entire IT operations network and business processes. Multi-user access to web interface allows stakeholders to view relevant infrastructure status. User-specific views ensures clients only see the infrastructure components they’re authorized for.

Nagios Core Features

  • Supported: Advanced Graphs & Visualizations
  • Supported: Performance & Capacity Planning Graphs
  • Supported: Configuration Wizards
  • Supported: Advanced Infrastructure Management
  • Supported: Configuration Snapshot Archive
  • Supported: Advanced User Management
  • Supported: Service-Level Agreement (SLA) Reports
  • Supported: Extendable Architecture

Nagios Core Integrations

Nagios Core Technical Details

Deployment TypesOn-premise, Software as a Service (SaaS), Cloud, or Web-Based
Operating SystemsWindows, Linux, Mac
Mobile ApplicationApple iOS, Android
Supported CountriesGlobal
Supported LanguagesEnglish, Spanish, Italian, Russian, German, French, Japanese, Simplified Chinese, Traditional Chinese, Korean, Portuguese, Polish

Frequently Asked Questions

Nagios provides monitoring of all mission-critical infrastructure components. Multiple APIs and community-build add-ons enable integration and monitoring with in-house and third-party applications for optimized scaling.

Reviewers rate Support Rating highest, with a score of 7.7.

The most common users of Nagios Core are from Mid-sized Companies (51-1,000 employees).
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Reviews and Ratings


Community Insights

TrustRadius Insights are summaries of user sentiment data from TrustRadius reviews and, when necessary, 3rd-party data sources. Have feedback on this content? Let us know!

Nagios, a popular IT infrastructure monitoring tool, has proven to be a valuable asset for organizations across various departments. With its robust monitoring capabilities and ease of setup, Nagios has become a go-to solution for many users. Users have found Nagios useful for a wide range of use cases, including monitoring applications and computing resources, gaining insights through reporting features, and proactively detecting potential issues. Nagios' ability to handle a large number of servers and services without stability issues has been commended by users. It also offers hassle-free implementation of plugins behind firewalls, supporting both Pull and Push Monitoring methods. The customization options in Nagios allow users to create plugins in various programming languages, making it adaptable to their specific needs. Integration with other technologies like MySQL, NRDP, Pnp4Nagios, and Grafana further enhances its functionality. For example, Nagios can be integrated with MySQL for storage and retrieval, NRDP for push alerting, Pnp4Nagios for RRD graphing, and Grafana for aggregated graphing, dashboards, heat-maps, and alerts.

Nagios plays a vital role in monitoring infrastructure for multiple departments within organizations. It is widely used by network operations teams to monitor infrastructure 24/7 and configure alerts for application status. Users have also found Nagios instrumental in identifying bottlenecks and patching issues during the testing phase. With its ability to monitor a diverse range of server operating systems and components like disk space, CPU and memory utilization, network availability, Kerberos replication, Active Directory, Novell NDS driver monitoring, among others; Nagios provides comprehensive coverage for system monitoring needs. It saves time by automating server space checks and sending real-time information to the IT team. Additionally, Nagios proves its worth in data centers by issuing early alerts on sensitive equipment such as servers, switches, routers, firewalls, and air conditioners. The tool is also used by various departments like Data Center Operations, Provisioning, Operations, Infrastructure, and Enterprise Monitoring to ensure the health and performance of their respective areas. Overall, Nagios stands out as an excellent open-source monitoring tool with a large community of users and scripts available for monitoring diverse applications, servers, websites, and services.

Flexibility and Configurability: Many users have praised Nagios for its extreme flexibility and configurability. They appreciate the ability to customize the monitoring according to their specific needs, including agent and agentless monitoring solutions with a variety of plugins.

Intuitive User Interface: The simplicity and ease of use of Nagios' user interface are highly praised by users. They mention that the interface is intuitive and easy to read, allowing them to quickly understand the monitoring status and identify any issues.

Extensibility through Plugins: The extensibility of Nagios through plugins, scripts, and customizations is highly valued by users. They mention that they have been able to add any needed functionality using plugins and scripts, making Nagios more flexible than other monitoring systems.

Dated and Unattractive User Interface: Several users have criticized Nagios for its dated and unattractive user interface, which they find less appealing. The interface is in need of a major overhaul to improve usability and streamline the experience. Some users have suggested improvements to make it less confusing and easier to navigate.

Reliance on Community-Driven Plugins: Users have expressed frustration with the reliance on open source community-driven plugins for third-party applications and hardware support in Nagios. This can lead to unpolished or broken plugins, requiring additional time to configure. Configuring and deploying these plugins was troublesome for some users, requiring patience to connect all the various components.

Steep Learning Curve: The learning curve for Nagios can be steep, especially for those not familiar with Linux. The configuration process can be messy and prone to accidental breakage, making it challenging for new users. Additionally, some background knowledge of Linux is required during the initial configuration process.

Attribute Ratings


(1-3 of 3)
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Score 8 out of 10
Vetted Review
Verified User
Nagios is being used to monitor and report on the utilization of some of our network hardware. It's primary use is restricted to our IT department, with a couple of additional users. We use it to monitor switch status, and mated with MRTG Nagios gives us bandwidth detail on a per port basis.
  • Up/Down Alerting.
  • Monitoring of supported applications (SQL, Exchange, etc).
  • Upon an alert, Nagios' ability to fire off scripts allows us to either fix problems automatically or gather data about an issue as soon as it happens.
  • Support for third party applications and hardware relies heavily on open source community driven plugins. Deploying new platforms to Nagios can be a bit of a job because of this, often plugins are unpolished, undocumented or outright broken. You have to be willing to spend some time tweaking to make this worth while.
  • The Nagios UI is not the best. Even with the new update, it's still quite evident that it's an updated version of an old system. While it's hard to re-arrange a tool like this, there comes a time when a UI overhaul is just what you have to do.
  • Nagios was quite obviously built to focus on alerting and event management. Attempting to use it also as a data collection tool can be frustrating and require a lot of plugins.
Nagios is primarily an open source technology. It's very well suited for environments that either work on a restricted budget and require a solution that can be customized heavily to fit. I would not recommend it to anyone with a limited time frame, tech skills, or someone looking for a canned monitoring or data collecting solution.
  • I know when I've got an outage before the phone rings. We often have dispatched techs and are working to resolve our issues long before our customers notice.
  • Nagios allows us to plan for future bottlenecks, there is very little reason to ever be surprised by a utilization issue.
  • Nagios has cost us heavily in man hours to get running and comfortable. However cost on back of man hours is better than live environment outages any day.
We selected Nagios because of the size of its community. We've used some of the others in the field over the past few years, Nagios had the best features out of the box coupled with it's following made it an easy selection.
Network Administrator Systems Administrator Phone Administrator NOC Crew Tier 1 and 2 support
Our systems admin handles the support of the Nagios platform, and we have an inhouse coder that works to make downloaded plugins fit our needs and when required writes custom code.
  • Up/Down Alerting
  • Resource Management
  • Uptime calculation
  • Resource Utilization predictions
  • By following strings of alerts as a failure happens we can easily identify the location of an outage and in moments get an idea of services effected.
  • We're really hoping to see Nagios catch up to some of our competitors in reporting and data collection.
We're currently looking to combine a bunch of our network montioring solutions into a single platform. Running multiple unique solutions for monitoring, data collection, compliance reporting etc has become a lot to manage.
  • Price
  • Product Features
  • Product Usability
  • Product Reputation
Price is always a concern, however when dealing with network monitoring and alerting, functionality needs to be at the top of the list. Nagios is a stable platform, with fantastic redundancy options. Nagios is at the top of their game.
With all the monitoring systems we evaluated, I don't think I spent enough time focused on importing data and customizing alerts. Instead of loading a couple of machines and doing some simple testing, I would have loaded our whole environment and attempted to use the solution in a real world scenario for a month. There have been a lot of customization related questions that came out after installation that could have been answered in the evaluation period.
  • Monitoring a supported platform is extremely easy to set up.
  • Setting up email alerting works exactly as it should.
  • Finding possible solutions in the community plugins is easy, however sometimes the configuration isn't so well documented.
  • Configuration in Nagios relies heavily on text files.
  • Graphing data is not supported out of the box, it requires additional plugins that can be complex to integrate.
The Nagios UI is in need of a complete overhaul. Nice graphics and trendy fonts are easy on the eyes, but the menu system is dated, the lack of built in graphing support is confusing, and the learning curve for a new user is too steep.
Eric Krueger | TrustRadius Reviewer
Score 10 out of 10
Vetted Review
Verified User
Nagios is being used primarily by the IT department but the management team makes use of its reporting features. With its robust monitoring and ease of use to set up our company has been happy with the product. Having the amount of information at our fingertips has made our jobs easier and given us the peace of mind that our systems are being monitored properly.
  • Monitoring of services is one of the biggest benefits for our company. Being able to respond in a timely fashion keeps business smooth.
  • Hardware and device monitoring are easy to set up with proper parameters.
  • Notification to key staff to be able to respond quickly makes issues go away faster.
  • There could be a better tutorial for setup but the overall system is very easy.
  • More options for notification would be great.
  • There could be a few more customization reporting functions.
This tool is very appropriate for IT staff to have the information they need at their fingertips. Notifications are timely and response time to issues has been cut down immensely. If you are looking for Nagios to be the one network monitoring tool for your department then you are in the right place. Nagios will allow your staff to focus on problem resolution and create efficiency by putting more information at their disposal.
  • Nagios has saved time by allowing our IT staff to focus on other projects.
  • Just knowing that systems are being properly monitored allows them to keep other tasks on track.
  • Downtime is lessened by proper timely notifications of system issues or down states.
Nagios is an easy to use intuative tool that gives a great return on investment. It has better monitoring features that IT needs than competitors and won't break the bank. Support for this tool is first class and the techs will help you to get the most out of the product.
IT infrastructure in charge of company wide support of all Systems and Applications. IT Ops also uses this product in their daily functions to keep on top of monitoring. Management is happy to receive reporting out of the Nagios system.
Network engineer in charge of maintaining the overall health of the network as well as all monitoring of issues. We also have a DBA who makes use of this system to keep all SQL monitoring information at his fingertips. Our system admin likes the timely notifications to keep her apprised of any potential issues.
  • Network Monitoring
  • Notification of issues
  • Review of systems to create better efficiency
  • Tracking issues over time to see trends in problems
  • Allow management to be able to see how IT is keeping business continuity running
  • Lateral notification of system outages or issues to non-IT personnel
  • Predicting systems to be refreshed earlier by examining past issues
  • Keeping up to date on systems for patching, updates ect
  • Aiding in risk analysis by examining past events
It has made our jobs easier and is a true IT betterment tool.
Score 3 out of 10
Vetted Review
Verified User
I have used Nagios for over 10 years. It has been a great tool to monitor and react to emergencies and is flexible and easy to implement. Nagios allows us to connect to each of our servers and connect to all the services, ports, metrics, etc., for each server we have.
  • Trusted
  • Easy to implement
  • Many plugins already written
  • Archaic
  • Dated UI
  • Quirky
Nagios is great if you're just learning about monitoring and want something that has been used for years. I have installed it in almost every company that I have worked for and it has been a great portal to the health and well being of our systems. At this point it is archaic software and there are better ways to implement monitoring (Sensu, Zabbix, Datadog, etc).
  • Open sourced, so it's free.
  • Ugly UI so not something to show an executive team.
  • Great for understanding overall system health.
Nagios was the best in the past and why I chose it for many of the companies I've worked for. Also, coming in to a company, there is almost always a Nagios server installed and since everyone knows the software it's easy to write plugins for it. But, in 2015, Nagios is a dinosaur and needs to be replaced with better, more scalable solutions.
The uptime of servers is essential to all parts of the business. Allowing everyone to see the uptime and accessibility of the infrastructure allows them to see how our servers are running. Everyone from support to IT to operations to business analysts are allowed a view to our Nagios installation.
Users will need to know linux, a command line interface editing tool (vi, emacs, pico, etc) and how to correctly edit conf files. It is rather quick and easy to do. For more dynamic work the conf files will need to be setup correctly, which can be tedious but worth it.
  • Monitoring server status
  • Dynamic data checking
  • Dashboard view of server status.
  • Can alert on anything with custom written alerts
  • Can send data to other products (cacti, graphite, etc)
  • n/A
  • Continue to deploy to new servers
  • Build out new environments
  • Find new ways to send data to other products.
Nagios is awesome yet antiquated and we plan to use other products that are free and open source that will do the same thing.
  • Price
  • Product Features
  • Product Usability
  • Product Reputation
The features of Nagios are ever expanding and allow users to see a full view of their infrastructure. Nagios has been around for YEARS now and many people within the industry have used and implemented it on their servers. It is easy to find employees that have used it in the past.
Well, now that their our so many other companies and products out there doing the same thing as Nagios, we would probably go with an open source product. We would probably go with sensu and then connect that to Pagerduty or VictorOps to do alerting. We would also send data on to our Graphite/Grafana infrastructure to anaylze the data.
We don't believe it is worth the extra money.
It's good and they are able to answer our questions that we have.
We were having an issue with creating a new configuration for a server that didn't have any plugins. I was able to reach out to Nagios Enterprises and get successfully configure the check to do what we needed it to do. Their support was very informed and ultimately fixed my problem.
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