The Prefect CLI is the easiest way to start a local instance of Prefect server.

​
Start the server

  1. Spin up a self-hosted Prefect server instance UI with the prefect server start CLI command in the terminal:
prefect server start
  1. Open the URL for the Prefect server UI (http://127.0.0.1:4200 by default) in a browser.

  1. Shut down the Prefect server with ctrl + c in the terminal.

​
Configure the server

Go to your terminal session and run this command to set the API URL to point to a self-hosted Prefect server instance:

prefect config set PREFECT_API_URL="http://127.0.0.1:4200/api"

You can save the API server address in a Prefect profile. Whenever that profile is active, the API endpoint is at that address. See Profiles and configuration for more information on profiles and configurable Prefect settings.

​
Database configuration

​
Use SQLite (default)

By default, Prefect uses a SQLite database stored at ~/.prefect/prefect.db. No additional configuration is needed for basic use.

​
Use PostgreSQL

To use PostgreSQL as your database backend:

  1. Set the database connection URL:
prefect config set PREFECT_API_DATABASE_CONNECTION_URL="postgresql+asyncpg://postgres:yourTopSecretPassword@localhost:5432/prefect"
  1. Start the server:
prefect server start

For more database configuration options, see the database settings reference.

​
Database management commands

​
Reset the database

Clear all data and reapply the schema:

prefect server database reset -y

​
Manage migrations

Apply database migrations:

# Upgrade to the latest version
prefect server database upgrade -y

# Downgrade to the previous version
prefect server database downgrade -y -r -1

# Downgrade to a specific revision
prefect server database downgrade -y -r d20618ce678e

For large databases, you may need to increase the timeout:

export PREFECT_API_DATABASE_TIMEOUT=600
prefect server database upgrade -y

​
Advanced configuration

For advanced deployment scenarios including:

  • Running behind a reverse proxy
  • Configuring SSL certificates
  • Multi-server deployments
  • Handling migration issues

See How to scale self-hosted Prefect.