Lessons Learned¶
Purpose: Mistakes, discoveries, and things worth remembering. Future-you will thank current-you.
After solving a problem or learning something valuable, add an entry using the template at templates/lesson-learned.md.
General Principles¶
Documentation: - Document while you work, not after — you'll forget the details - Document WHY you made a decision, not just WHAT you did - If a recovery procedure isn't tested, it's fiction
Unraid: - Always stop the array cleanly before shutting down - Parity checks matter — schedule them and don't skip - Community Applications (CA) plugin versions can drift — pin versions in compose files - Backup the USB boot drive — losing it means reinstalling Unraid config from scratch - Flash Backup plugin is worth using
Proxmox: - VMs are easier to backup and restore than LXC containers - Always enable QEMU guest agent - Snapshots are not backups — they live on the same disk - Give VMs slightly more resources than you think they need
Docker / Containers:
- Use named volumes or bind mounts for persistent data — never rely on container storage
- Pin image versions — :latest will bite you eventually
- docker logs <name> is always your first debugging step
Networking: - Document your firewall rules — you will forget them - Changing DNS settings breaks things in non-obvious ways — change carefully - Test connectivity after every network change before assuming it worked
Backups: - A backup you haven't tested restoring is not a backup - Offsite matters — local backup doesn't protect against fire, flood, or theft - Retention policies matter — check you're not filling up storage silently