Nagios Core
The open source industry standard in IT infrastructure monitoring and alerting
Free

Benefits
Monitoring
IT staff configure Nagios to monitor critical IT infrastructure components, including system metrics, network protocols, applications, services, servers, and network infrastructure.
Alerting
Nagios sends alerts when critical infrastructure components fail and recover, providing administrators with notice of important events. Alerts can be delivered via email, SMS, or custom script.
Response
IT staff can acknowledge alerts and begin resolving outages and investigating security alerts immediately. Alerts can be escalated to different groups if alerts are not acknowledged in a timely manner.
Reporting
Reports provide a historical record of outages, events, notifications, and alert response for later review. Availability reports help ensure your SLAs are being met.
Maintenance
Scheduled downtime prevents alerts during scheduled maintenance and upgrade windows.
Planning
Trending and capacity planning graphs and reports allow you to identify necessary infrastructure upgrades before failures occur.