Open-Source MSP Monitoring Software: Why IT Service Providers Add Icinga to Their RMM Stack

If you run a managed service provider, your RMM software is the backbone of daily operations. Remote management, patch cycles, ticketing workflows – it handles the essentials. But if you’re monitoring more than a few dozen client environments, you’ve likely noticed that monitoring and management are not the same thing. And that difference matters more the larger you grow.

This post is not about replacing your RMM. It’s about what happens when your monitoring requirements outgrow what RMM was designed to do and how open-source monitoring with Icinga fits alongside it as dedicated MSP monitoring software.

Tools like NinjaOne are purpose-built for MSPs. They centralize endpoint management, automate patch deployment, integrate with PSA platforms, and give your technicians a single console to manage client fleets. For the core MSP workflow – deploy, manage, remediate – NinjaOne works well.

That’s exactly what they’re optimized for: Management.

Where MSPs Hit the Monitoring Ceiling

The challenge starts when clients ask harder questions: Can you prove uptime against our SLA? Can you alert us if this database is slow, not just offline? Can you monitor our network devices, our custom application, our hybrid cloud environment?

Most RMM tools weren’t designed for deep infrastructure monitoring. They’re strong on Windows endpoints and agent-based checks, but they fall short in areas MSPs run into regularly. The same community spreadsheet confirms it: NinjaOne, for example, lists no support for network route visualization or user application experience monitoring. These aren’t edge cases for growing MSPs, they’re recurring client requests.

The specific gaps most MSPs encounter

How Icinga Fills the Gaps

Icinga is an open-source monitoring platform built for flexibility at scale. It’s not an RMM – it doesn’t do patch management or remote sessions. But it covers the monitoring depth that RMM tools leave behind, and it’s specifically well-suited to MSP environments.

Multi-tenant monitoring by design

Icinga’s zone-based architecture lets you separate every client environment at the infrastructure level. Each client gets their own monitoring zone with a dedicated satellite. This means overlapping IP address spaces are handled cleanly, client data stays isolated, and your team sees exactly what they need to see. Icinga’s built-in monitoring at scale architecture is designed to grow with you – from a handful of clients to hundreds.

Automated onboarding via Icinga Director

Icinga’s monitoring automation layer turns manual setup into a repeatable process. New client environments can be provisioned automatically – integrating with tools like Ansible, NetBox, or your own CMDB. Once configured, onboarding a new client’s monitoring takes hours, not days.

SLA reporting built in

Icinga generates availability and SLA reports that MSPs can deliver directly to clients. Monthly uptime, downtime windows, acknowledgment history – all documented without custom scripting.

Deep network monitoring

SNMP, custom service checks, application-layer monitoring – Icinga monitors anything you can write a check for. This covers the infrastructure that RMM agents can’t reach. For MSPs with clients running complex network environments, this is where Icinga earns its place in the stack.

No per-endpoint licensing

As an open-source platform, Icinga has no per-host or per-client licensing fees. For MSPs where margin depends on keeping tool costs predictable as you add clients, this is a meaningful difference compared to proprietary monitoring tools.

API-first integration

Icinga’s REST API means it connects to the rest of your stack – ticketing systems, alert routing tools, custom dashboards, and automation frameworks – without forcing you to change how your team works.

A note on vendor independence

The r/MSP RMM spreadsheet makes something clear that’s easy to overlook: most major RMM platforms are backed by private equity or publicly listed companies. Kaseya (Insight Venture Partners) owns both Datto RMM and VSA. ConnectWise Automate and ConnectWise RMM are Thoma Bravo-owned. N-able is NYSE-listed. Barracuda RMM belongs to KKR. For MSPs who have watched consolidation drive up prices and degrade support quality across their tooling stack, the ownership structure of their software vendors matters. Icinga is fully independent – open-source, with no investors or shareholders influencing the roadmap. If you want to understand how this plays out in the broader monitoring market, our post on investment trends in the infrastructure monitoring market goes into more detail.

What the Combined Stack Looks Like in Practice

Rather than replacing NinjaOne or other RMM tools, MSPs typically run both with clear roles:

The two tools don’t overlap – they cover different layers of the MSP stack.

How MSPs Use Icinga in Production

Two IT service providers who built their managed services on Icinga illustrate what this looks like at real scale.

SVA System Vertrieb Alexander GmbH

50.000+ checks across 100 client zones

“When a new customer comes on board, their environment is ready within hours, with all monitoring configured.”

SVA System Vertrieb Alexander GmbH, one of Germany’s leading IT service providers, runs a multi-cloud managed services division on Icinga. Their setup monitors over 2,300 hosts and 50,000 checks across 100 client zones – each with its own dedicated satellite. New clients are onboarded automatically through Ansible scripts that provision the entire monitoring stack, including Icinga, within hours of signing. Clients receive tailored dashboards showing only what’s relevant to them, and Icinga generates the monthly availability reports SVA uses to prove SLA compliance. Read the full SVA customer story on the Icinga website.

q.beyond AG

63.000+ checks, single cluster

“We had decided on a new platform that scales better. That’s where Icinga’s excellent scalability suited us very well.”

q.beyond AG, a full-stack managed service provider based in Cologne, chose Icinga specifically because multi-tenancy and scale were their primary requirements. Their installation manages 9,000 host objects and 63,000 service checks – all from a single cluster using Icinga’s master and satellite zone model. The monitoring team automated their entire configuration workflow using Icinga Director, eliminating manual maintenance and freeing up engineering time for higher-value work. q.beyond describes Icinga as a core building block in their event pipeline. Read full q.beyond customer story here.

Getting Started

Icinga is open-source and free to download. The fastest path for MSP use cases is to start with a single zone and a handful of client hosts before expanding to the full satellite architecture. The Icinga documentation covers the cluster setup in detail. If you want to understand the automation layer first, the Icinga Director webinar is the best starting point.

If you’re evaluating Icinga for a larger MSP deployment and want to talk through the architecture, get in touch with the Icinga team.

Ready to add monitoring depth to your MSP stack?

Free and open-source. No per-endpoint licensing, no lock-in. Deploy alongside your existing RMM.