Centreon

Centreon is a Paris-built infrastructure monitoring platform with an open-source core — Apache 2.0, created by Julien Mathis and Romain Le Merlus — and a self-hosted IT-100 edition that stays free for up to 100 hosts with no time limit, which is a genuinely usable starting point rather than a crippled trial.

Beyond that free tier, the commercial editions add SLA monitoring, geographical and business views, and reporting: self-hosted Business starts from €283 per month for 125 hosts, and a SaaS IT Edition from €425 per month for the same footprint, so the same product scales from a self-hosted free tier to a managed cloud deployment without switching tools. More than 700 monitoring connectors cover the usual mix of cloud, network and application targets out of the box.

Centreon SAS is based in Paris. The trade-off against Zabbix or Icinga is that the free tier caps out at 100 hosts before the pricing kicks in, and against Checkmk the discovery experience is less automatic — Centreon expects more deliberate configuration of what to monitor.

What Centreon does well

• Open-source core (Apache 2.0), free self-hosted up to 100 hosts
• 700+ monitoring connectors out of the box
• Same product as self-hosted or SaaS
• French company, EU jurisdiction
• SLA monitoring and business views on paid editions

Where Centreon falls short

• Free tier capped at 100 hosts
• Less automatic discovery than Checkmk
• SaaS hosting region not published
• Commercial pricing scales with host count

Standout feature. A free self-hosted tier that actually stays free up to 100 hosts, not a time-limited trial.