Explained
Server problems, explained without the jargon.
What a worrying alert actually means, what to check first, and when it is time to act — written for the person responsible for the server, not just the person who runs it.
Your server has started swapping
What high swap usage means, why everything slows down, and what to check first.
Read the guide →Your disk is filling up
Where Docker disk space goes, which clutter is safe to clear, and what needs care.
Read the guide →Your app keeps restarting itself
What a restart loop means, how to distinguish an OOM kill from an app crash, and what to read next.
Read the guide →Your site is slow after a deploy
Why deploys make everything sluggish for a while, what recovers on its own, and what doesn’t.
Read the guide →Your server ran out of memory
What the out-of-memory killer is, how to read its tracks, and what to do about the victim.
Read the guide →You can’t SSH into your server
The four usual causes, in order of likelihood, and the honest back door every provider gives you.
Read the guide →Your site is showing 502 Bad Gateway
What the error means, why your proxy is the one reporting it, and the three usual causes.
Read the guide →Your SSL certificate has expired
Why browsers block the site outright, why automatic renewal fails silently, and how to stop it recurring.
Read the guide →Your server’s processor is pinned at 100%
When a busy processor is a server doing its job, when it is a runaway, and how to tell them apart.
Read the guide →