dynamo/docs/components/frontend

title
Frontend

The Dynamo Frontend is the API gateway for serving LLM inference requests. It provides OpenAI-compatible HTTP endpoints and KServe gRPC endpoints, handling request preprocessing, routing, and response formatting.

Feature Matrix

Feature	Status
OpenAI Chat Completions API	✅ Supported
OpenAI Completions API	✅ Supported
KServe gRPC v2 API	✅ Supported
Streaming responses	✅ Supported
Multi-model serving	✅ Supported
Integrated routing	✅ Supported
Tool calling	✅ Supported

Quick Start

Prerequisites

• Dynamo platform installed
• etcd and nats-server -js running
• At least one backend worker registered

HTTP Frontend

python -m dynamo.frontend --http-port 8000

This starts an OpenAI-compatible HTTP server with integrated pre/post processing and routing. Backends are auto-discovered when they call register_model.

The frontend does the pre and post processing. To do this it will need access to the model configuration files: config.json, tokenizer.json, tokenizer_config.json, etc. It does not need the weights.

Frontend will download the files it needs from Hugging Face, no setup is required. However we recommend setting up modelexpress-server and a shared folder such as a Kubernetes PVC. This ensures the model is only downloaded once across the whole cluster.

If the model is not available on Hugging Face, such as a private or customized model, you will need to make the model files available locally at the same file path as on the backend. The backend's --model-path <here> will need to exist on the frontend and contain at least the configuration (JSON) files.

KServe gRPC Frontend

python -m dynamo.frontend --kserve-grpc-server

See the Frontend Guide for KServe-specific configuration and message formats.

Kubernetes

apiVersion: nvidia.com/v1alpha1
kind: DynamoGraphDeployment
metadata:
  name: frontend-example
spec:
  graphs:
    - name: frontend
      replicas: 1
      services:
        - name: Frontend
          image: nvcr.io/nvidia/dynamo/dynamo-vllm:latest
          command:
            - python
            - -m
            - dynamo.frontend
            - --http-port
            - "8000"

Configuration

Parameter	Default	Description
--http-port	8000	HTTP server port
--kserve-grpc-server	false	Enable KServe gRPC server
--router-mode	round_robin	Routing strategy: round_robin, random, kv

See the Frontend Guide for full configuration options.

Next Steps

Document	Description
Frontend Guide	KServe gRPC configuration and integration
Router Documentation	KV-aware routing configuration