PingPlotter, Zabbix, Lansweeper, Cockpit Project, Paessler PRTG Network Monitor, Datadog, Observium, Cacti, The Dude, LibreNMS, Total Network Inventory, Spiceworks, PHP Server Monitor, NIXStats, Pinguzo, MRTG, Icinga, System Center Operations Manager, Storm.dev, PhpSysInfo, Monitis, Munin, Total Network Monitor, NetXMS, Nagwin, LANState, IT Asset Tool, Alerta, WhatsUp Gold, Cabot, RPi-Monitor, Pandora FMS, OP5 Monitor, Xymon, Glimpse, Shinken, LogicMonitor, Controlup, pgDash, CloudMonix, SigNoz, Advanced Host Monitor, Intermapper, Monitorix, Centreon Enterprise Server, CloudStats, SeaLion, ElastAlert, openITCOCKPIT, Thruk, SyWatchdog, NetCrunch, AppBeat, Opsview Monitor Mobile, ActiveXperts Network Monitor, Agentless Monitor, HappyApps, Wavefront by VMware, Ipsentry, CoScale, Axibase Time Series Database, Hosted Graphite, Sentinet3, AppPerfect Agentless Monitor, CloudView NMS, Server Density, InfraCheck, OpsDash, Statance, SentinelAgent, internetVista Monitoring, Dataloop.io, AppOptics, CloudScreener, PA Server Monitor, AggreGate Network Manager, SQL Wristband, GFI MAX RemoteManagement, DeferPanic, Blue Matador, Monique.io, Bosun, Naemon, Alignak, eG Enterprise, Monometric.IO, LiveMon, AuditShark are some alternatives to Nagios.