I already presented in an article the tools I am going to talk about now, but this time it will be a less technical and more “philosophical” approach.
In the era of observability hype, where every dashboard shines with dynamic graphs and intense colors, talking about Monit and MMonit sounds almost like heresy.
No containers, no exporters, no data pipelines with 14 components. Just a binary, a clear configuration file and a simple idea:
watch that the system works, and if something fails, fix it.
And yet, Monit and its centralized panel complement MMonit remain, twenty years later, one of the least valued, most effective, stable and efficient solutions for monitoring, alerting and executing actions on Unix and Linux servers.
A sysadmin Swiss army knife
Monit embodies the UNIX philosophy in its pure state.
It supervises processes, ports, filesystems, sockets, web services, load, memory… and can even execute corrective actions without depending on an external system. All local, fast, clear and without complex dependencies.
It does not need agents, databases, brokers…
It is that discreet process that runs in the background, consumes less memory than most modern “exporters” and, when it needs to act, you know it will be there.
MMonit, its centralized complement, adds the panoramic view: management of hundreds/thousands of nodes, status visualization, user segmentation, centralized alerts and remote actions.
It does not have the bright aesthetics of a modern interface, but it works, and does so with a stability and speed that many “cloud-native” solutions would envy.
Efficiency and low cost
Monit, the client (and not just client) is open source and the license cost of MMonit (if you need it) is almost symbolic compared to any enterprise monitoring platform.
Even more so considering that:
- It does not require costly infrastructure (no heavy databases, no queues, no clusters).
- Its deployment is done in minutes.
- Its maintenance is practically nil.
In a practical use case example, for an environment of 200 servers, the resource consumption and operating cost of MMonit is a fraction of that of systems like Prometheus, Alertmanager, Grafana, Zabbix and others not to mention SaaS solutions.
And yet, it offers the same operational security: knowing what is happening, where, and being able to react quickly.
The fashion of noise
The current DevOps world seems to have forgotten something fundamental: having more metrics and complex systems does not mean you understand your system better.
Today “total” observability tools abound, promising to see every metric, log and trace in real time.
But the price of that visibility is, often, an avalanche of complexity:
- architectures with ten interdependent components,
- cascading storage,
- fragile pipelines,
- costly and difficult to reproduce maintenance.
In that context, Monit seems “outdated” only because it does not shine. But the truth is that it keeps doing something that many modern stacks cannot do without a legion of microservices: watch over and repair a system by itself, without depending on anything else.
The KISS principle: the UNIX soul we are losing
UNIX is (or was) based on a simple credo: “Keep It Simple, Stupid.”
Each program should be small, clear and do one thing well. And when several programs were combined, they did so in a predictable and robust way.
Monit is, perhaps, one of the current examples in the monitoring framework of that spirit that still survives. It has no glamour, but it has essence.
Its configuration is readable, its behavior is deterministic and its dependencies are minimal. It does not need a cluster to take care of a system: itself is enough.
In a world where every new tool seems to reinvent the wheel with more layers and more RAM, remembering that principle is not nostalgia: it is common sense.
Modernizing without betraying the philosophy
Nothing prevents combining the best of both worlds. Monit and MMonit can continue to be the heart of monitoring — the core that watches, repairs and alerts — while integrating with modern tools like Grafana (for visualization) or Loki (for centralizing logs). This gives you a “modern facade” without losing the sobriety of the core.
Because modernizing does not mean complicating, and a simple, transparent and autonomous system will always be easier to maintain than a trendy ecosystem that needs three microservices to tell you that a process died.
Conclusion
Monit and MMonit represent a school that is scarce today: that of the sysadmin who prefers to understand what is happening rather than decorating it.
It is not a trendy stack, it has no spectacular dashboards, nor an API full of buzzwords. It has something much more valuable: reliability, clarity and control.
Perhaps it is time to reconcile with that sobriety and admit that, in practice, technical elegance does not lie in adding more layers, but in needing less to achieve the same.
And if that is not UNIX, what is?