I really don't get Docker volumes over bind mounts.

Docker says they're easier to backup/migrate over bind mounts¹, but I don't understand how rsyncing a single directory that contains everything is supposed to be harder than doing whatever this series of commands are in their documentation.

To me, Docker volumes make sense when you're dealing with temporary data, such as a cache. Or when you're needing to process data before making it permanent. Something like a /tmp.

docker compose down should remove volumes by default. I imagine Docker intends docker compose down -v as a full reset, but a single additional small (-v) flag is so easy to inadvertently lose data. Instead they should force the sysadmin to manually delete the data by specifying the volume name after an rm -rf. And by "volume name", I, of course, mean the bind mount.

docker compose down to remove all volumes. docker compose down --keep-temp-volumes to keep the (should be temporary) volumes.

Anyways. I use bind mounts. I prefer them over volumes. If volumes died tomorrow, I would feel nothing but elation.²

1. "Volumes" ↩

2. This whole piece came about because I was dealing with a 1TB server that was low on disk space, and I figured I would try docker volume prune to see if it cleared anything up. Reader, even after I brought every container down via -v, I cleared out 700GB+. That shouldn't be possible!!! ↩