Server monitoring & management
Server monitoring built for Coolify.
Coolify runs your apps. Onserva watches the machine underneath — and tells you, in plain English, when something is wrong, why it is happening, and what to do about it. Say the word and it carries out the fix itself.
Built and run in the UK by No Fear Tech Ltd. Watching production Coolify servers today.
Coolify tells you that something happened. It doesn’t tell you why, and it can’t tell you anything when the box itself is in trouble.
Coolify’s built-in monitoring is genuinely useful — it will ping you when disk crosses a threshold or a container restarts. But it watches from inside the same machine it’s reporting on, its alerts are readings rather than explanations, and a server that is struggling badly enough struggles to raise its own alarm.
So most people still find out one of three ways: a deploy fails, a customer emails, or the whole box stops answering. All three are too late.
Onserva watches from outside the server, around the clock, and tells you before any of those happen.
What Onserva watches on a Coolify box
Memory pressure and swapping
Containers ask for memory in bursts. When the machine runs short, it starts parking data on disk — and everything slows down long before anything actually crashes. We watch the trend, not the spike.
Disk filling up
Old images, build cache, logs and backups grow silently until a deploy fails with "no space left on device". We warn from the trend weeks earlier, so you have time to investigate before it is urgent.
Restart loops
An app that keeps dying and being brought back can look green on a dashboard. We show the memory pressure and container load around it, so an out-of-memory problem is much easier to investigate.
Sustained load
A processor pinned at 100% for an hour is not the same as one working hard for a minute. We judge every reading on a sustained trend, so you are not woken by a server doing its job.
Response times
Your sites are checked from outside, the way your visitors reach them — not just from inside the box, where everything can look fine.
Silence
Onserva runs somewhere else. A machine that dies cannot switch off its own alarm — silence is itself something we tell you about.
What an alert actually looks like
Coolify
Coolify has begun shifting some of its working data onto the disk because it ran short of fast memory, and the amount moved there has grown from about a fifth to just over a quarter in the last hour.
Why: something on the server asked for a lot of memory at once recently, and rather than run out, the machine parked the least-used data on disk. The readings cannot show which of the three applications caused it.
What to do: no urgent action is needed, but this is worth keeping an eye on over the next day or two. If the amount parked keeps climbing, a restart of the applications would return the server to a clean state.
A real message from a real Coolify server. Not a mock-up.
How it works
Four steps, and only one of them is yours.
- 1
Paste one command
It installs a small agent that reads what the operating system already publishes about itself. It does not touch Coolify, your containers, or your apps. No dependencies, no reboot.
- 2
We watch, every twenty seconds
Processor, memory, disk, network, response times — judged on sustained trends.
- 3
You get told what and why
A message on Telegram or by email within a minute, in words you can act on.
- 4
You press Authorise
Where a known, tested fix applies — clearing build cache, restarting a looping container — one button does it and tells you what happened. Where none does, we say so plainly rather than guessing.
The agent only ever makes outbound connections — no port is opened on your machine. The AI can read your readings and suggest actions from a short, pre-tested list; it is never given the keys. Every fix waits for you, every time. How this is enforced, in detail
Questions Coolify owners actually ask
Doesn't Coolify already have monitoring built in?
Yes — and keep it on. Sentinel and Coolify’s notifications are good at telling you that something crossed a line: disk above a threshold, a container restarted. Onserva is different in three ways. It watches from outside your server, so it still works — and speaks up — when the machine itself is failing; an agent on the box goes silent along with it. It explains rather than reports: not “disk 85%”, but what’s taking the space, how fast it’s growing, and what to do. And it carries out the fix when you authorise it. The usual alternative is wiring up Prometheus, Grafana and cAdvisor yourself — an evening of setup and dashboards you then have to interpret. Onserva is one pasted command.
Why is my Coolify server using so much memory?
Usually it isn't one app — it's the total. Each container holds on to memory it was given at its busiest moment, build processes ask for large amounts in short bursts, and the operating system keeps recently used files in memory because that's faster. Trouble starts when the total pushes the machine into swapping: parking data on disk instead. That's when everything gets slow. The fix is rarely “more RAM” first — it's finding out which container is growing, which Onserva's readings show you over time.
Coolify says my app is running — why is the site down?
“Running” means the container process exists. It doesn’t mean the site answers. The app can be deadlocked, the proxy can be misrouting, or the machine can be so starved it takes thirty seconds to serve a page. Onserva checks your sites from the outside, the way a visitor does, so “running but not responding” gets caught.
Will the agent interfere with Coolify or my containers?
No. It reads figures the operating system already publishes about itself and sends them out. It doesn’t sit in the request path, doesn’t modify containers, and adds a negligible load of its own.
Do I need to open a port or give you SSH access?
No port is ever opened; the agent only makes outbound connections. Fixes you authorise are carried out through the agent’s outbound channel, from a short, pre-tested list — never by anyone signing in to your machine.
Stop finding out from a failed deploy.
Your first server is monitored free, forever. One command, two minutes, nothing to configure.