The industry standard in open-source IT monitoring tools for servers, networks, applications, and services.
Visit WebsiteThe Bottom Line
Entry price
Free plan available, paid tiers above
Biggest pro
Legacy monitoring standard
Biggest con
UI very dated
TL;DR - Nagios
- Open-source IT monitoring for servers, networks, applications, and services.
- Offers both a free, community-supported core and an enterprise-grade paid version (Nagios XI).
- Highly extensible with a vast plugin architecture and strong community support.
What is Nagios?
Pros & Cons
Pros
- Legacy monitoring standard
- Highly customizable
- Large plugin library
- Free and open source
- Battle-tested
Cons
- UI very dated
- Configuration complex
- Scaling difficult
- Setup time-consuming
- Alternatives more modern
Ratings Across the Web
Ratings aggregated from independent review platforms. Learn more
Key Features
Pricing Plans
Free TrialCore (Free)
Free
- Open source
- Community support
- Unlimited hosts
XI Standard
$1,995/one-time
- 7 Nodes or 100 Services
- Advanced Reporting
- Custom Dashboards
- Configuration Wizards
XI Professional
$3,495/one-time
- Audit Logging
- Bulk-Modification Tools
- Capacity Planning
- Automated Host Decommissioning
Reviews
Across 192 verified user reviews on G2, SourceForge, Capterra
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Still deciding?
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Nagios FAQ
What is Nagios?
Is Nagios free?
What can Nagios monitor?
Who should use Nagios?
Source: nagios.org