Support thread for the Docker Orphan Cleaner plugin for Unraid (docker.orphan.cleaner).

What the plugin does

Unraid removes orphan Docker images (images that no container references) only one at a time, from the Docker tab. That is slow when a host has accumulated a lot of them, and there is no way to see the whole set or to tell how safe each one is to remove.

Docker Orphan Cleaner lists every orphan in one place, classifies how safe each one is to delete, and removes the selected images in bulk. It also reports the reclaimable build cache and can prune it on request.

It is deliberately conservative. Nothing is force-removed, every manual deletion is confirmed, and a scheduled run only ever deletes untagged images.

How images are classified

Each orphan is placed in exactly one class, in this precedence order:

Class	Meaning	Ticked by default
Pinned	Matches a user pin pattern. Never deleted, in the UI or on a schedule	no
Template	repo:tag matches a <Repository> in /boot/config/plugins/dockerMan/templates-user/*.xml; the container was removed but its template remains	no
Compose	repo:tag appears as an image: in a Docker Compose stack; a stack that is down makes its images look orphaned	no
Tagged	Has a real tag, but nothing references it	no
Untagged	No tag (<none>), with or without a repo digest	yes

Untagged includes superseded pulls: when a tag moves to a newer pull, the old image keeps its digest, loses its tag, and is exactly the kind of image you want to clean up. One row is produced per image ID; untagged rows show repository@sha256:<short> so you can tell what the image was.

Safety properties

• Dry run is on by default and enforced on the server. Delete and Prune do nothing unless the request explicitly carries "dryRun": false. A missing or malformed flag is treated as a dry run.

• The orphan set is recomputed at delete time from the Docker daemon. What the browser sends is treated as a request, never as authority. An image that is no longer an orphan, or that is pinned, is refused.

• Nothing is force-removed. Deletion is one image per API call, force=0. A parent image that cannot be removed is reported per image instead of failing the whole batch.

• Scheduled runs are notify-only by default. Even in delete mode they only touch untagged images, and they respect pins and the minimum age.

• The plugin never modifies container templates or icons. It only reads them.

Screenshots

Install

The plugin is not yet listed in Community Applications (submission in progress). Until it is, install it manually:

1. In the Unraid webGUI, go to Plugins ▸ Install Plugin.

2. Paste this URL and click Install:

   https://raw.githubusercontent.com/bitcryptic-gw/unraid-docker-orphan-cleaner/main/plugin/docker.orphan.cleaner.plg
   

It appears as a tile under Settings ▸ User Utilities. Settings (pins, minimum age, schedule) are on the same page.

Requires Unraid 7.0.0 or newer (tested on 7.3.2)

Source and issues

• GitHub: https://github.com/bitcryptic-gw/unraid-docker-orphan-cleaner

• Issues: https://github.com/bitcryptic-gw/unraid-docker-orphan-cleaner/issues

Known limitations

• The "Unique" size is a lower bound. It is Size − SharedSize from /system/df. Layers shared only among the images you selected are also freed but are not counted, so the real saving can be larger than the Unique figure. The "total" figure is the sum of each image's full size and overstates the saving, because it counts shared layers more than once.

• Only images are cleaned. Unused Docker volumes are not touched.

• Tagged orphans are never auto-deleted. A scheduled run only removes untagged images that are older than the minimum age.

• The plugin needs the Docker service to be running.

Edited yesterday at 07:16 AM1 day by BitCryptic
Include screen shots

Do we really need a slopped plugin to run docker image prune -f -a?

5 hours ago, BitCryptic said:

The plugin is not yet listed in Community Applications

Hopefully does not.

Edited yesterday at 11:59 AM1 day by Kilrah

@Squid

10 hours ago, Kilrah said:

Do we really need a slopped plugin to run docker image prune -f -a?

Hopefully does not.

I guess on that basis, we don't need Unraid. Everyone can install headless Linux and use docker compose and monitor everything with a collection of bash scripts ?

Or perhaps the whole point is to be more inclusive and give people a platform that lets them use a GUI or CLI as their experience or confidence permits...
There's a lot of plugins and docker templates I don't find useful, so I don't install and use them.