Nagios XI vs Prometheus
Nagios XI
nagios.com
Prometheus
prometheus.ioSide by side
| Figure | Nagios XI | Prometheus |
|---|---|---|
| Price from | Free | Free |
| Free plan | Yes | Yes |
| Free trial | Yes | — |
| Open source | — | — |
| Web | Yes | Yes |
| Windows | Yes | Yes |
| macOS | Yes | Yes |
| Linux | Yes | Yes |
| API | Yes | — |
| Self-hosted | Yes | Yes |
| Plans published | 9 | 1 |
| Spec score · Container Monitoring | 9.0 (#4) | 7.7 (#35) |
| Spec score · Infrastructure Monitoring | 9.0 (#3) | 7.7 (#23) |
| Spec score · Monitoring Observability | 9.0 (#3) | 7.7 (#17) |
| Spec score · Server Monitoring | 9.0 (#4) | 7.6 (#28) |
| Spec score · Cloud Monitoring | 9.0 (#4) | 7.6 (#15) |
| Spec score · Metrics Monitoring Tools | 9.0 (#5) | 7.7 (#21) |
| Deployment | Nagios XI is self-hosted on Linux and offers virtual machine images for VMware Workstation, Oracle VirtualBox, VMware ESXi and vSphere, and Microsoft Hyper-V. | Official components have precompiled binaries and Docker images, and the Prometheus download page lists Windows, macOS, and Linux builds. |
| Founded | 2007 | 2012 |
| Integrations | Nagios XI supports authentication with Active Directory or LDAP over SSL, Single Sign-On with Microsoft Entra ID, and two-factor authentication through Duo. | The ecosystem includes client libraries, exporters, Pushgateway, and Alertmanager; integrations also include Grafana for visualization and webhook-based alert notifications. |
| Support | A paid license includes the first year of Maintenance & Support, version upgrades, up to ten support cases, Support Portal access, Premium features, and an assigned Customer Success Manager. | The project offers community support through channels including Slack, mailing lists, and a Discourse forum, and lists independent commercial support providers separately. |
| What it does | Nagios XI is commercial infrastructure monitoring software that executes threshold-based checks on servers, network devices, applications and services, records results and sends notifications. | Prometheus is an open-source systems monitoring and alerting toolkit that collects and stores metrics as time series. |
Plans
Nagios XI
- Standard — 100 Nodes$2,595, paid once
- Enterprise — 100 Nodes$4,690, paid once
- FreeFree
- FreeFree
- Standard$2,595, paid once
- Standard (100-Node)$2,595, paid once
- Enterprise$4,690, paid once
- Enterprise (100-Node)$4,690, paid once
- SitewidePriced on request
In their own words
Nagios XI
Nagios XI monitors servers, network devices, applications and services from a Linux server you manage. It checks configured thresholds, records results and sends notifications. Standard includes more than 90 configuration wizards, auto-discovery, dashboards, performance graphs, an open REST API, automation, configuration rollback and snapshots. Enterprise adds SLA and capacity-planning reports, scheduled reports and pages, business process intelligence, bulk changes and an audit log. Users can be restricted to assigned host and service groups, with authentication options including Active Directory or LDAP over SSL, Microsoft Entra ID single sign-on and Duo two-factor authentication. It is self-hosted on Linux, with virtual machine images for several hypervisors and offline installation on Red Hat and CentOS Stream. A 30-day trial provides unlimited monitoring, Enterprise features and direct support without a credit card. The free plan is limited to 7 nodes or 100 services, whichever comes first. Paid perpetual licenses are priced by monitored nodes: Standard is $2,595.00 once and Enterprise is $4,690.00 once, each shown for 100 nodes.
Prometheus
Prometheus is a free, open-source toolkit for systems monitoring and alerting that collects metrics as time series. Each series is identified by a metric name and key-value labels, and PromQL is used to query the data. Prometheus typically gathers metrics by pulling over HTTP; it can also receive pushed data through an intermediary gateway. Targets can be found with service discovery or configured statically. The main server runs as a standalone monolithic binary without external dependencies, and official components are available as precompiled binaries and Docker images. Its ecosystem includes client libraries, exporters, Pushgateway and Alertmanager, with Grafana for visualization and webhooks for alert notifications. Prometheus and most exporters support TLS, client certificate authentication and HTTP Basic Authentication. The project advises against exposing component HTTP endpoints to public networks without protective measures. Servers do not depend on network storage or remote services, which the project says can help during outages. Prometheus is not recommended for uses requiring 100% accurate data, such as per-request billing.