Supervisord: A Powerful Process Management Tool

It is no exaggeration to describe it as “powerful.” Born in the Python ecosystem, Supervisord has grown into a highly mature process management tool. With just some simple installation and configuration, you can turn any non-daemon process into a daemon. Any little utility scripts you’ve written can instantly get a fancy service-like upgrade.

As a quick explainer—why do we want to daemonize? Simply put, it elevates your program from the application layer to the service layer (regardless of whether your program natively behaves like a service).

Now, let’s get into the good stuff:

1. Installation

There are two recommended ways:

• Method A: Use easy_install, a Python packaging utility that makes downloading, installing, and updating Python packages a breeze. If you already have easy_install installed, simply run the following in your terminal:

  easy_install supervisor

• Method B: If you don’t have easy_install and don’t care to install it, go to http://pypi.python.org/pypi/supervisor to download the package, extract it, and install it manually:

  python setup.py install

For more installation methods, you can refer to the official docs at http://supervisord.org/installing.html.

2. Configuration

Run the following commands in your shell:

echo_supervisord_conf > /etc/supervisord.conf
mkdir /etc/supervisord.conf.d
cat << EOF >> /etc/supervisord.conf

[include]
files = /etc/supervisord.conf.d/*.conf
EOF

If you want to enable the web-based monitoring dashboard, uncomment the following lines (remove the semicolons) in /etc/supervisord.conf:

[inet_http_server]         ; inet (TCP) server disabled by default
port=127.0.0.1:8080        ; (ip_address:port specifier, *:port for all iface)
username=user              ; (default is no username (open server))
password=123               ; (default is no password (open server))

3. Creating Process Configuration Files

To keep things modular and easy to maintain, all process-specific configurations should be saved in the /etc/supervisord.conf.d/ directory as *.conf files:

vi /etc/supervisord.conf.d/yourprogram.conf

Here is a configuration example:

[program:yourprogram]
directory = /var/program
command = /var/program/yourprogram
autostart = true
startsecs = 5
user = root
redirect_stderr = true
stdout_logfile = /var/log/supervisord/yourprogram.log

For more detailed program settings, refer to the official configuration documentation: http://supervisord.org/configuration.html#program-x-section-settings

4. Running Supervisord

Simply run the command in your shell as root:

supervisord