Configuration Overview

Gunicorn reads configuration information from five places.

Gunicorn first reads environment variables for some configuration settings.

Gunicorn then reads configuration from a framework specific configuration file. Currently this only affects Paster applications.

The third source of configuration information is an optional configuration file gunicorn.conf.py searched in the current working directory or specified using a command line argument. Anything specified in this configuration file will override any framework specific settings.

The fourth place of configuration information are command line arguments stored in an environment variable named GUNICORN_CMD_ARGS.

Lastly, the command line arguments used to invoke Gunicorn are the final place considered for configuration settings. If an option is specified on the command line, this is the value that will be used.

When a configuration file is specified in the command line arguments and in the GUNICORN_CMD_ARGS environment variable, only the configuration file specified on the command line is used.

Once again, in order of least to most authoritative:

  1. Environment Variables
  2. Framework Settings
  3. Configuration File
  4. GUNICORN_CMD_ARGS
  5. Command Line

Note

To print your resolved configuration when using the command line or the configuration file you can run the following command:

  1. $ gunicorn --print-config APP_MODULE

To check your resolved configuration when using the command line or the configuration file you can run the following command:

  1. $ gunicorn --check-config APP_MODULE

It also allows you to know if your application can be launched.

Command Line

If an option is specified on the command line, it overrides all other values that may have been specified in the app specific settings, or in the optional configuration file. Not all Gunicorn settings are available to be set from the command line. To see the full list of command line settings you can do the usual:

  1. $ gunicorn -h

There is also a --version flag available to the command line scripts that isn’t mentioned in the list of settings.

Configuration File

The configuration file should be a valid Python source file with a python extension (e.g. gunicorn.conf.py). It only needs to be readable from the file system. More specifically, it does not have to be on the module path (sys.path, PYTHONPATH). Any Python is valid. Just consider that this will be run every time you start Gunicorn (including when you signal Gunicorn to reload).

To set a parameter, just assign to it. There’s no special syntax. The values you provide will be used for the configuration values.

For instance:

  1. import multiprocessing
  3. bind = "127.0.0.1:8000"
  4. workers = multiprocessing.cpu_count() * 2 + 1

All the settings are mentioned in the settings list.

Framework Settings

Currently, only Paster applications have access to framework specific settings. If you have ideas for providing settings to WSGI applications or pulling information from Django’s settings.py feel free to open an issue to let us know.

Paster Applications

In your INI file, you can specify to use Gunicorn as the server like such:

  1. [server:main]
  2. use = egg:gunicorn#main
  3. host = 192.168.0.1
  4. port = 80
  5. workers = 2
  6. proc_name = brim

Any parameters that Gunicorn knows about will automatically be inserted into the base configuration. Remember that these will be overridden by the config file and/or the command line.