Compare software

Nagios Core vs Icinga 2: catalog facts
Nagios Core	Icinga 2
Free Free and open source. Hosting, hardware and any external services are separate.	Free Free and open source. Hosting, hardware and any external services are separate.
Self-hosted	Self-hosted
Runs plugin-based checks Tracks availability and sends notifications	Supports distributed monitoring setups Runs service checks and notifications
Configuration and many checks need manual setup or additional plugins.	A complete deployment involves configuration and optional web-interface components.
Self-hosted	Self-hosted
Open source	Open source
License: GPL-2.0	License: GPL-3.0
Not stated if an account is needed	Not stated if an account is needed
Not stated if it works offline	Not stated if it works offline
Official website Full listing and sources Checked September 22, 2026	Official website Full listing and sources Checked September 22, 2026

Catalog facts only. Anything “not stated” is unconfirmed. Check full listings for details.