Best server monitoring tools in 2026
Host and service monitoring, from the long-running self-hosted systems to hosted agents that report CPU, disk and process health. This list has the top 14 of 31 server monitoring tools, ranked by a published score. Of these, 10 are open source, 13 have a free plan and 13 can be self-hosted. Checked by hand on 30 September 2026.
How this list is ranked
Each active tool gets a score out of 100. Archived, end-of-sale and maintenance-only tools are left out.
- Capabilities: up to 75 points for the share of the category checklist that the tool's own documentation confirms. A tool meeting 8 of 10 items gets 60.
- Free to start: 15 points for a free plan or a free edition.
- Open or self-hostable: 10 points if it is open source or can be self-hosted.
Each category has a fixed checklist of capabilities (shown in the table below and on every tool page). An item counts only when the tool's own documentation confirms it; anything we could not confirm counts as not met. How long a tool has existed is deliberately not scored, so a new tool is not ranked below an older one for being new. Tools with the same score share a rank (shown as =), are listed A to Z within it, and the list never cuts between them. Nobody pays for a position.
- =1
Checkmk
Infrastructure monitoring for servers, networks, cloud and containers with automatic service discovery; the base edition is open source and paid editions add more.
100 10 of 10 capabilities (75), free 15, open 10 - =1
Netdata
Per-second metrics for servers, containers and applications from an agent with built-in dashboards and alerts, plus the optional hosted Netdata Cloud.
100 10 of 10 capabilities (75), free 15, open 10 - =1
Zabbix
Open source monitoring for networks, servers, VMs, applications and cloud, using agents, SNMP and templates with trigger-based alerting; Zabbix Cloud is the hosted option.
100 10 of 10 capabilities (75), free 15, open 10 - =4
Icinga
Monitoring system that grew out of Nagios: checks hosts and services with plugins, scales across distributed zones, and is configured through files or an API.
93 9 of 10 capabilities (68), free 15, open 10 - =4
ManageEngine OpManager
On-premises network and server monitoring for routers, switches, firewalls, Windows and Linux hosts and virtual machines.
93 9 of 10 capabilities (68), free 15, open 10 - =4
NetXMS
Network and infrastructure management system with SNMP discovery, network maps, server agents and event correlation; an Enterprise edition adds support and features.
93 9 of 10 capabilities (68), free 15, open 10 - =4
PRTG Network Monitor
Windows-based network and server monitoring from Paessler built around sensors for SNMP, WMI, flows, ping and HTTP, with maps and dashboards.
93 9 of 10 capabilities (68), free 15, open 10 - 8
Bleemeo
Hosted monitoring for servers, containers and Kubernetes built on an open source agent, with uptime checks, dashboards and alert rules.
90 10 of 10 capabilities (75), free 15, open 0 - =9
Apache HertzBeat
Agentless monitoring system from the Apache Software Foundation that polls servers, databases, middleware, network devices and websites through templates, with built-in alerting.
85 8 of 10 capabilities (60), free 15, open 10 - =9
Glances
Cross-platform system monitor in Python that shows CPU, memory, disk, network, processes and containers in a terminal, a web UI or a REST API.
85 8 of 10 capabilities (60), free 15, open 10 - =9
openITCOCKPIT
Monitoring suite that manages Naemon checks through a web interface, with Checkmk and Grafana integration; community and enterprise editions.
85 8 of 10 capabilities (60), free 15, open 10 - =9
OpenNMS
Network management platform for fault and performance monitoring at scale; Horizon is the open source edition and Meridian the supported one.
85 8 of 10 capabilities (60), free 15, open 10 - =9
Pandora FMS
Monitoring for servers, networks, applications and logs, with an open source community edition and a commercial enterprise edition.
85 8 of 10 capabilities (60), free 15, open 10 - =9
SolarWinds
Suite of network, server, database and application monitoring products, sold as self-hosted software and as the SaaS SolarWinds Observability.
85 10 of 10 capabilities (75), free 0, open 10
Side by side
| Tool | Pricing | Free plan | Open source | Self-hosted | Host agent | Agentless checks | Windows hosts | Auto-discovery | Process and service checks | Log collection | Containers | Alerting with notifications | Dashboards | Plugins or integrations |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Checkmk | Free plan | Yes | Yes | Yes | Yes | Yes | Yes | Yes | Yes | Yes | Yes | Yes | Yes | Yes |
| Netdata | Free plan | 5 nodes, non-commercial use | Yes | Yes | Yes | Yes | Yes | Yes | Yes | Yes | Yes | Yes | Yes | Yes |
| Zabbix | Free plan | Yes | Yes | Yes | Yes | Yes | Yes | Yes | Yes | Yes | Yes | Yes | Yes | Yes |
| Icinga | Free plan | Yes | Yes | Yes | Yes | Yes | Yes | - | Yes | Yes | Yes | Yes | Yes | Yes |
| ManageEngine OpManager | Free plan | Free edition: 3 devices | No | Yes | Yes | Yes | Yes | Yes | Yes | Yes | - | Yes | Yes | Yes |
| NetXMS | Free plan | Yes | Yes | Yes | Yes | Yes | Yes | Yes | Yes | Yes | - | Yes | Yes | Yes |
| PRTG Network Monitor | Free plan | Freeware edition: 100 sensors | No | Yes | - | Yes | Yes | Yes | Yes | Yes | Yes | Yes | Yes | Yes |
| Bleemeo | Free plan | 3 servers, 5 uptime monitors | No | No | Yes | Yes | Yes | Yes | Yes | Yes | Yes | Yes | Yes | Yes |
| Apache HertzBeat | Free | Yes | Yes | Yes | No | Yes | Yes | - | Yes | Yes | Yes | Yes | Yes | Yes |
| Glances | Free | Yes | Yes | Yes | Yes | Yes | Yes | Yes | Yes | - | Yes | - | Yes | Yes |
| openITCOCKPIT | Free plan | Yes | Yes | Yes | Yes | Yes | Yes | - | Yes | - | Yes | Yes | Yes | Yes |
| OpenNMS | Free plan | Yes | Yes | Yes | - | Yes | Yes | Yes | Yes | Yes | - | Yes | Yes | Yes |
| Pandora FMS | Free plan | Yes | Yes | Yes | Yes | Yes | Yes | Yes | Yes | - | - | Yes | Yes | Yes |
| SolarWinds | Paid | No | No | Yes | Yes | Yes | Yes | Yes | Yes | Yes | Yes | Yes | Yes | Yes |
Yes: confirmed in the tool's documentation. No: documented as not offered. -: not confirmed. Plans and prices change; check each tool's own site before you decide.
More lists
- Server monitoring tools in 2026 31
- Open source server monitoring tools in 2026 20
- Server monitoring tools with a free plan in 2026 26
- Self-hosted server monitoring tools in 2026 25
- Best monitoring tools in 2026 28
- Best uptime monitoring tools in 2026 10
- Best cron job monitoring tools in 2026 6
- Best network monitoring tools in 2026 11
- Best database monitoring tools in 2026 12
- Best Kubernetes monitoring tools in 2026 14
- Best cloud monitoring tools in 2026 5