Network analytics · Nagios Enterprises

Nagios

Long-standing open-source device and service monitoring engine, with a commercial XI edition adding a web UI and reporting.

Nagios Core is a free, open-source monitoring engine configured through text files and plugins that checks host and service availability and alerts on failures — general device/service monitoring, not outside-in synthetic testing or inside-network flow analytics. Nagios XI is built on the same engine and is what most organizations actually deploy: it adds web-based configuration, 90+ setup wizards, auto-discovery, a backing database, dashboards, performance graphing, SLA/capacity reports, multi-tenancy, a REST API and a support contract. Core remains free and unlimited; XI is licensed perpetually by node count with the first year of maintenance included.

At a glance

Vendor Nagios Enterprises
Pricing model Free tier + paid plans
Free tier Yes
Deployment Self-hosted
Open source Yes (GPL-2.0)
Best for IT teams wanting a proven, self-hosted monitoring engine, free at the core with a paid path to a web UI and reporting.

Pricing

Nagios Core is free and open source; Nagios XI is a perpetual license priced by monitored node count, with an Enterprise add-on tier.

Plan Price Notes
XI Standard from $2,595 perpetual license for 100 nodes, first year maintenance included
XI Enterprise from $4,690 add-on to any license level, for 100 nodes; adds SLA/capacity reports, SSO, multi-tenancy

Prices read from the vendor's own page on September 21, 2026. Vendors change prices; check the source before you budget.

Features

  • Host and service availability checks
  • Large open-source and commercial plugin ecosystem
  • Web-based configuration and auto-discovery (XI)
  • Performance graphing and dashboards (XI)
  • SLA and capacity planning reports (XI Enterprise)
  • REST API (XI)
  • Multi-tenancy and SSO (XI Enterprise)

Integrations

Profile last reviewed September 21, 2026

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