About

This site records things that actually broke on my own small infrastructure: a router, a Proxmox host, a handful of VMs, a NAS, a tailnet, a few laptops. Each post says what the symptom looked like, why the first diagnosis was wrong, what the root cause was, how it was proven, what the fix was, and how the fix was verified.

The name comes from Hieda no Akyuu, the chronicler of Gensokyo and author of the Perfect Memento in Strict Sense (求聞史紀). Her job is to write down what happened, accurately, not to write best practices. So the rules here are:

• Nothing gets a post unless it broke first. Every entry maps to a real, dated event.
• Titles describe the symptom, not the conclusion. The symptom is what you type into a search box.
• Commands and output are pasted as they were, including the evidence that looked fine and misled me.
• A fix comes with a way to verify it. “Changed it and it worked” does not count.
• Most posts are drafted by an AI from the notes taken during the incident, and I read every one before it goes up.

Two kinds of entry:

• postmortem: the full write-up, six sections: Symptom, Why it is easy to misdiagnose, Root cause, Proof, Fix, Lessons.
• note: a few paragraphs about a pitfall: symptom, cause, fix.

Systems change. Each post describes the state on its date. RSS is at /feed.xml.