Open WebUI integration

Open WebUI is an open-source, self-hosted web interface that provides a ChatGPT-like experience for local AI models. You can connect it to Docker Model Runner to get a polished chat interface for your models.

Prerequisites#

• Docker Model Runner enabled with TCP access
• A model pulled (e.g., docker model pull ai/llama3.2)

Quick start with Docker Compose#

The easiest way to run Open WebUI with Docker Model Runner is using Docker Compose.

Create a compose.yaml file:

services:
  open-webui:
    image: ghcr.io/open-webui/open-webui:main
    ports:
      - "3000:8080"
    environment:
      - OLLAMA_BASE_URL=http://host.docker.internal:12434
      - WEBUI_AUTH=false
    extra_hosts:
      - "host.docker.internal:host-gateway"
    volumes:
      - open-webui:/app/backend/data

volumes:
  open-webui:

Start the services:

$ docker compose up -d

Open your browser to http://localhost:3000.

Configuration options#

Environment variables#

Using OpenAI-compatible API#

If you prefer to use the OpenAI-compatible API instead of the Ollama API:

services:
  open-webui:
    image: ghcr.io/open-webui/open-webui:main
    ports:
      - "3000:8080"
    environment:
      - OPENAI_API_BASE_URL=http://host.docker.internal:12434/engines/v1
      - OPENAI_API_KEY=not-needed
      - WEBUI_AUTH=false
    extra_hosts:
      - "host.docker.internal:host-gateway"
    volumes:
      - open-webui:/app/backend/data

volumes:
  open-webui:

Network configuration#

Docker Desktop#

On Docker Desktop, host.docker.internal automatically resolves to the host machine. The previous example works without modification.

Docker Engine (Linux)#

On Docker Engine, you may need to configure the network differently:

services:
  open-webui:
    image: ghcr.io/open-webui/open-webui:main
    network_mode: host
    environment:
      - OLLAMA_BASE_URL=http://localhost:12434
      - WEBUI_AUTH=false
    volumes:
      - open-webui:/app/backend/data

volumes:
  open-webui:

Or use the host gateway:

services:
  open-webui:
    image: ghcr.io/open-webui/open-webui:main
    ports:
      - "3000:8080"
    environment:
      - OLLAMA_BASE_URL=http://172.17.0.1:12434
      - WEBUI_AUTH=false
    volumes:
      - open-webui:/app/backend/data

volumes:
  open-webui:

Using Open WebUI#

Select a model#

1. Open http://localhost:3000
2. Select the model drop-down in the top-left
3. Select from your pulled models (they appear with ai/ prefix)

Pull models through the UI#

Open WebUI can pull models directly:

1. Select the model drop-down
2. Enter a model name: ai/llama3.2
3. Select the download icon

Chat features#

Open WebUI provides:

• Multi-turn conversations with context
• Message editing and regeneration
• Code syntax highlighting
• Markdown rendering
• Conversation history and search
• Export conversations

Complete example with multiple models#

This example sets up Open WebUI with Docker Model Runner and pre-pulls several models:

services:
  open-webui:
    image: ghcr.io/open-webui/open-webui:main
    ports:
      - "3000:8080"
    environment:
      - OLLAMA_BASE_URL=http://host.docker.internal:12434
      - WEBUI_AUTH=false
      - DEFAULT_MODELS=ai/llama3.2
    extra_hosts:
      - "host.docker.internal:host-gateway"
    volumes:
      - open-webui:/app/backend/data
    depends_on:
      model-setup:
        condition: service_completed_successfully

  model-setup:
    image: docker:cli
    volumes:
      - /var/run/docker.sock:/var/run/docker.sock
    command: >
      sh -c "
        docker model pull ai/llama3.2 &&
        docker model pull ai/qwen2.5-coder &&
        docker model pull ai/smollm2
      "

volumes:
  open-webui:

Enabling authentication#

For multi-user setups or security, enable authentication:

services:
  open-webui:
    image: ghcr.io/open-webui/open-webui:main
    ports:
      - "3000:8080"
    environment:
      - OLLAMA_BASE_URL=http://host.docker.internal:12434
      - WEBUI_AUTH=true
    extra_hosts:
      - "host.docker.internal:host-gateway"
    volumes:
      - open-webui:/app/backend/data

volumes:
  open-webui:

On first visit, you'll create an admin account.

Troubleshooting#

Models don't appear in the drop-down#

1. Verify Docker Model Runner is accessible: console $ curl http://localhost:12434/api/tags

2. Check that models are pulled: console $ docker model list

3. Verify the OLLAMA_BASE_URL is correct and accessible from the container.

"Connection refused" errors#

1. Ensure TCP access is enabled for Docker Model Runner.

2. On Docker Desktop, verify host.docker.internal resolves: console $ docker run --rm alpine ping -c 1 host.docker.internal

3. On Docker Engine, try using network_mode: host or the explicit host IP.

Slow response times#

1. First requests load the model into memory, which takes time.

2. Subsequent requests are much faster.

3. If consistently slow, consider: - Using a smaller model - Reducing context size - Checking GPU acceleration is working

CORS errors#

If running Open WebUI on a different host:

1. In Docker Desktop, go to Settings > AI
2. Add the Open WebUI URL to CORS Allowed Origins

Customization#

Custom system prompts#

Open WebUI supports setting system prompts per model. Configure these in the UI under Settings > Models.

Model parameters#

Adjust model parameters in the chat interface:

1. Select the settings icon next to the model name
2. Adjust temperature, top-p, max tokens, etc.

These settings are passed through to Docker Model Runner.

Running on a different port#

To run Open WebUI on a different port:

services:
  open-webui:
    image: ghcr.io/open-webui/open-webui:main
    ports:
      - "8080:8080"  # Change first port number
    # ... rest of config

What's next#

• API reference - Learn about the APIs Open WebUI uses
• Configuration options - Tune model behavior
• IDE integrations - Connect other tools to DMR