---
title: Media Pipeline Pitfalls
created: '2026-05-23'
updated: '2026-05-27'
type: tech
namespace: family
tags: [media-pipeline, pitfalls, torrents, infra]
related:
  - "[[tech/arr-stack-kraken]]"
  - "[[concepts/watchlist-automation]]"
---

# Media Pipeline Pitfalls

## Torrents — Do Not Rename Files

Never rename torrent source files or folders while a torrent is active.
Transmission tracks files by path. Renaming breaks the association and
causes re-download or stalled seeding.

## torrent-set-location Updates downloadDir

`torrent-set-location` in the Transmission RPC updates `downloadDir` in
the torrent metadata. Use this when moving completed files, not a manual
rename. Sequence:

1. Move files to new location on disk
2. Call `torrent-set-location` with the new path + `move=false`
3. Verify torrent goes back to seeding state

## Router Creates Subdirectories — Transmission downloadDir Stale

`router.py` creates subdirectory per title under the genre folder
(lowercase name, e.g. `/media/cartoons/бобик в гостях у барбоса/`).
Transmission still holds the old `downloadDir` pointing to the parent
(`/media/cartoons/`). Result: torrents show "No data found" error.

Fix:
1. Find the actual subdirectory on disk
2. Call `torrent-set-location` with the subdirectory path + `move=false`
3. Transmission verifies and resumes seeding

## Alpine Container — No Docker-in-Docker

`on-download-complete.sh` runs inside the Transmission Alpine container.
Docker CLI is not available there — using `docker run` inside the container
fails silently or errors. Python 3.14 IS available in the Alpine image.

Solution: `sync.py` (Python3, ~190 lines) in the same container:
- Reads `config.json` for sorting rules + credentials (same file as linker container)
- Queries TMDB for genre routing
- Creates hardlinks + calls Transmission RPC `torrent-set-location`
Location: `/srv/dev-disk-by-uuid-49e8f586-3839-4c5d-a1e1-58bfc3579ade/docker/media-pipeline/sync.py`

## General Rules

- Never touch source files/folders (media-pipeline USER.md rule)
- `resolve-manual` is emergency-only
- NFO files: do not create manually; let the pipeline handle them
- Never delete test files from the pipeline project