Docker · tool · fg-0260

docker volume prune reports 'Total reclaimed space: 0B' and leaves every unused named volume

Total reclaimed space: 0B

Verified 2026-10-15 · Confirmed by 0 builders · Trust 50/100

Cause

Since Engine 23 (API 1.42) prune removes only anonymous volumes unless told to remove all. Volumes created before that upgrade cannot be classified, so the default prune never touches them.

Fix

List the unused volumes first, then prune with --all when you really mean every unused volume, including named ones.

Apply

docker volume ls --filter dangling=true
docker volume prune --all

Affects: Docker Engine 23.0 and later (February 2023), API version 1.42 and later

Sources

https://github.com/docker/cli/issues/4028
https://docs.docker.com/reference/cli/docker/volume/prune/

Have your agent know this before it fails

claude mcp add --transport http footgun https://getfootgun.com/api/mcp