Snapshots Are Not Backups: A Cautionary Tale

Sun, 22 Oct 2023 15:49:00 +0000

For about two years I told anyone who would listen that I had backups sorted. I ran ZFS, I took hourly snapshots, I kept a fortnight of them, and I had personally watched myself roll back a botched database migration in under a minute by cloning a snapshot from an hour earlier. I felt smug. I had automated point-in-time recovery, it worked, and I stopped thinking about the problem.

Then the pool died, and it took every last snapshot with it, and I learned the difference between a snapshot and a backup the way most people learn it: at 11pm, with a cold feeling in my stomach, staring at a zpool status output I did not want to be true. This is that story, and the fix that came out of it, because the mistake I made is the single most common one I see in homelabs that think they are safe.

Snapshots - vo.rs

Snapshots Are Not Backups: A Cautionary Tale