I'm running into permission issues with Docker named volumes. My app container runs as
UID 1000 but the volume data is owned by root. I've tried using --user flag
and init containers but nothing sticks after restart.
$ ls -la /var/lib/docker/volumes/myapp_data/_data/
total 12
drwxr-xr-x 2 root root 4096 Mar 12 14:00 .
drwxr-xr-x 3 root root 4096 Mar 12 14:00 ..
-rw-r--r-- 1 root root 156 Mar 12 14:00 config.yaml
Running Docker 24.0 on Ubuntu 22.04. Any best practices here?
The cleanest solution is to use a named volume with the :U flag (if using
Podman) or set up an init container that fixes permissions.
volumes:
- myapp_data:/data:U
The :U flag automatically maps the volume owner to the container's user
namespace. For Docker specifically, you'll want the entrypoint approach.
Adding to Sarah's answer — there's also a less-known trick using
docker-compose.yml driver options:
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Hope this helps! Let me know if you need more details on the setup.
Thanks both! The entrypoint approach worked perfectly. Marking Sarah's answer as accepted.