Icinga
Icinga is a fork of Nagios and is backward compatible.
18 Alternatives To Icinga
Cacti
Cacti is a complete network graphing solution. It provides a fast poller, advanced graph templating, multiple data acquisition methods, and user management features.
Check_MK
Check_MK is comprehensive IT monitoring solution in the tradition of Nagios.
Librato
Your monitoring infrastructure in the cloud. Store, visualize and alert on all your metrics at all levels of the stack. Get your 30d free trial.
LibreNMS
A fully featured network monitoring system that provides a wealth of features and device support.
LogicMonitor
LogicMonitor is the SaaS performance monitoring platform for the world’s best IT teams. Deploy Fast, Monitor More, Improve Ops.
Monit
Monit is a free open source utility for managing and monitoring, processes, files, directories and filesystems on a UNIX system. Monit conducts automatic maintenance and repair and can execute meaningful causal actions in error situations.
Munin
PnP networked resource monitoring tool that can help to answer the what just happened to kill our performance
NetWrix Auditor
Configuration Auditing of IT Infrastructure
Observium
Observium
OpsGenie
Alerting and On-Call Management for Dev&Ops Teams
PRTG
PRTG Network Monitor is a network monitoring and infrastructure management tool. It lets network administrators monitor devices such as access points, routers and switches. Read more about PRTG.
PRTG Network Monitor
An advanced network monitoring solution to monitor network up/downtime, traffic and usage.
PagerDuty
Cloud based monitoring service
Pandora FMS
Pandora FMS: Opensource monitoring software
Prometheus
An open-source systems monitoring and alerting toolkit.
Pulseway
Pulseway changes the enterprise monitoring and management game with its mobile management solution.
Site24x7
Site24x7 offers both free & paid website monitoring services. Monitor websites remotely and receive instant email/sms alerts if your website becomes unavailable. View uptime & performance graphs of your website monitors.
Spiceworks Help Desk
Help desk software features that work for IT