Things that broke, and what they cost.
Every article here started as an incident on this lab. No tutorials rewritten from documentation — only problems we hit, diagnosed, and fixed, with the dead ends included.
A Proxmox node that pings, accepts SSH, and still refuses every key
Node out of the cluster, port 8006 accepting TCP, SSH rejecting every key, /etc/pve empty. One missing fstab line was the whole story.
ReadA network mount was dead for 11 days while every service wrote to the empty folder underneath
systemd recorded the mount failed once and never retried. Nothing alerted, because nothing was broken from the writers' point of view.
ReadWhy an unprivileged LXC can read a network share but not write to it
The container sees the files as nobody and cannot write. The cause is UID mapping, and the fix belongs on the host, not in the container.
ReadUniFi has two API key stores, and using the wrong one costs an hour
200 from the cloud API and 401 from every gateway endpoint, with both header styles. That specific combination has exactly one cause.
ReadAn unattended disc ripper that refuses to file anything until you confirm
Drop in a DVD or CD, walk away — but nothing reaches the library until a human confirms the title, because disc labels lie.
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