Hi everyone,
I’m trying to connect Helmarr (iOS) to my Transmission instance running on UmbrelOS, and I’m stuck behind Umbrel’s auth proxy. Hoping someone here has cracked this.
Setup
- UmbrelOS on a home server (LAN only)
- Transmission installed from the Umbrel App Store
- Helmarr on iOS, same Wi-Fi
The problem
Every Umbrel app sits behind an app_proxy container that enforces Umbrel’s own login. In a browser, hitting http://umbrel.local/transmission shows me the Umbrel login first, then the Transmission web UI (which itself has no auth enabled — the proxy is supposed to handle that).
Helmarr connects to Transmission by talking to its RPC endpoint directly (/transmission/rpc). The catch: Transmission has no API key concept. Unlike Sonarr/Radarr — where I can paste the app’s API key into Helmarr and authenticate directly against the API, completely sidestepping the proxy — Transmission’s RPC only supports either no auth or HTTP Basic Auth. And on Umbrel, Transmission’s own RPC auth is disabled, so even if Helmarr could send credentials, there’s nothing on the Transmission side to validate them. The Umbrel proxy gates the request before it ever reaches Transmission.
So there’s no clean handshake available: no API key, no RPC password, and the proxy in front demands the Umbrel master password, which Helmarr can’t supply.
What I’m looking for
What’s the cleanest way to let an external client (Helmarr, or any third-party Transmission client like Transmission Remote GUI, tremotesf, etc.) reach Transmission’s RPC on UmbrelOS?
- Official/supported way to whitelist my LAN subnet for a specific app’s proxy?
- Anyone exposing port 9091 directly and re-enabling Transmission’s native RPC auth as the security layer, without breaking Umbrel’s Sonarr/Radarr auto-integration?
- Any Nginx Proxy Manager pattern people are using here?
Thanks — happy to share whatever I land on.