# spark-control

A browser-based control panel for a dual-DGX-Spark vLLM cluster. Designed to run as a [StartOS 0.4](https://docs.start9.com/packaging/0.4.0.x/) package on a Start9 server on the same LAN as the Sparks.

## What it does

- Shows which LLM is currently loaded on the cluster (`:8888/v1/models`).
- Click to swap to a different model — stops the current one, launches the new one, streams logs to the UI until `Application startup complete.` appears.
- Surfaces health for Parakeet (STT, `:8000`) and Magpie (TTS, `:9000`) on Spark 2.

## Architecture

```
[Browser/phone] ──► [StartOS reverse proxy] ──► [spark-control container]
                                                       │  (SSH over LAN)
                                                       ▼
                                                  [Spark 1] ──► launch-cluster.sh
                                                       │
                                                       ▼
                                                  [Spark 2]
```

Two layers in this repo:

- `image/` — a self-contained FastAPI app + static UI. Runs anywhere with `uvicorn` and an SSH client. Useful for development.
- `package/` — a thin StartOS 0.4 wrapper that packages the image, exposes the UI on the LAN, and gives the user actions to configure SSH access to the Sparks.

## Quick start (local dev, no StartOS yet)

```bash
cd image
python -m venv .venv && source .venv/bin/activate
pip install -e .
export SPARK1_HOST=<spark-1-host>.local
export SPARK1_USER=<spark-user>
export SPARK2_HOST=<spark-2-ip>
export SPARK2_USER=<spark-user>
export SSH_KEY_PATH="$HOME/Library/Application Support/NVIDIA/Sync/config/nvsync.key"
uvicorn app.server:app --host 0.0.0.0 --port 9999 --reload
```

Open <http://localhost:9999>.

## Repo layout

- `models.yaml` — model catalog (also bundled into the image)
- `image/` — Docker image source
- `package/` — StartOS 0.4 package source
- `scripts/build-s9pk.sh` — convenience wrapper around the StartOS build
- `runbook.md` — operating notes
- `known-issues.md` — known quirks and workarounds

## Status

v0.1 — local-only, single-cluster, no auth (trusts LAN).