When Docker runs on a modern Linux distro, every container start, stop, or health‑check event is logged by the Docker daemon (dockerd). Those logs are forwarded to systemd‑journal, which is great for auditability but can quickly flood the journal with repetitive, low‑value messages. On a busy host a single day of activity can generate several megabytes of journal data, making it hard to spot real issues and bumping disk usage.
A home NAS is usually a single‑disk or a small RAID array.
When you run several containers—media servers, databases, CI runners—each one writes a JSON log file under
/var/lib/docker/containers/<id>/<id>-json.log.
If you leave the default json-file driver untouched, those files grow indefinitely.
On a 1 TB NAS, a handful of containers can fill the drive in weeks, forcing you to delete data or upgrade hardware.
I’ve seen this go wrong when managing Docker on a small Linux server: volumes can become a challenge. Docker volumes are directories that are shared between the host system and containers, allowing for persistent data storage. If not properly managed, they can lead to disk space issues and security risks. The real trick is to stay on top of volume management to avoid these problems.
To create a new volume, you can use the docker volume command. For example, to create a new volume named my-volume, you can use the following command: