Nagios XI

Nagios XI is self-hosted IT infrastructure and network monitoring software built on open-source Nagios Core, sold as a perpetual license by node count.

Nagios XI runs checks against every server, service and network device on a schedule, and tells the people assigned when a result crosses a limit they set. Each check returns OK, Warning, Critical or Unknown against ranges the team defines, so every alert traces back to a rule someone wrote. Underneath sits Nagios Core, the open-source engine Ethan Galstad created in 1999. Nagios Enterprises, LLC, the independent Saint Paul company he founded in 2007, develops XI and adds the web interface, database, reporting, dashboards and API on top of Core. Configuration Wizards set up monitoring for a host, an application or a network device, and Auto-Discovery scans a subnet to feed what it finds into them. Servers report through the Nagios Cross-Platform Agent (NCPA) or through NRPE and NSClient++, while network gear usually needs no agent at all. Wizards also cover Docker containers, Kubernetes clusters through NCPA, and switch and router ports with their bandwidth and status. Smart Dashboards combine graph, gauge, treemap and alert heatmap dashlets, and Status Views suit a wall display. The Enterprise edition adds SLA reports, Capacity Planning, Business Process Intelligence, scheduled reports, bulk modification and an audit log. XI is built for IT and network teams that keep their monitoring on a Linux server of their own. It fits sysadmins who already rely on Nagios Core plugins and want a graphical front end, reports and dashboards over them. Host and service group permissions let several teams share one install, each working with the groups it owns. Larger estates spread their checks across sites with Mod-Gearman workers or federated servers. Nagios Enterprises builds solutions around it for government, emergency services, transportation and telecommunications. A network team uses it to page the on-call engineer through Slack, Discord or Twilio SMS the moment a router stops answering. A platform team watches Docker hosts and Kubernetes nodes from the same console that tracks its physical servers. When flow data or central logs are needed, XI works beside Nagios Network Analyzer and Nagios Log Server. Managers receive availability measured against their SLA target, or the dashboard they want every Monday as a PDF in their inbox.