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+:title: Using Supervisor with Docker
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+:description: How to use Supervisor process management with Docker
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+:keywords: docker, supervisor, process management
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+
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+.. _using_supervisord:
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+
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+Using Supervisor with Docker
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+============================
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+
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+.. include:: example_header.inc
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+
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+Traditionally a Docker container runs a single process when it is launched, for
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+example an Apache daemon or a SSH server daemon. Often though you want to run
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+more than one process in a container. There are a number of ways you can
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+achieve this ranging from using a simple Bash script as the value of your
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+container's ``CMD`` instruction to installing a process management tool.
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+
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+In this example we're going to make use of the process management tool,
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+`Supervisor <http://supervisord.org/>`_, to manage multiple processes in our
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+container. Using Supervisor allows us to better control, manage, and restart the
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+processes we want to run. To demonstrate this we're going to install and manage both an
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+SSH daemon and an Apache daemon.
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+
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+Creating a Dockerfile
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+---------------------
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+
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+Let's start by creating a basic ``Dockerfile`` for our new image.
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+
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+.. code-block:: bash
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+
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+ FROM ubuntu:latest
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+ MAINTAINER examples@docker.io
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+ RUN echo "deb http://archive.ubuntu.com/ubuntu precise main universe" > /etc/apt/sources.list
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+ RUN apt-get update
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+ RUN apt-get upgrade -y
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+
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+Installing Supervisor
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+---------------------
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+
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+We can now install our SSH and Apache daemons as well as Supervisor in our container.
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+
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+.. code-block:: bash
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+
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+ RUN apt-get install -y openssh-server apache2 supervisor
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+ RUN mkdir -p /var/run/sshd
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+ RUN mkdir -p /var/log/supervisor
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+
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+Here we're installing the ``openssh-server``, ``apache2`` and ``supervisor``
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+(which provides the Supervisor daemon) packages. We're also creating two new
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+directories that are needed to run our SSH daemon and Supervisor.
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+
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+Adding Supervisor's configuration file
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+--------------------------------------
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+
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+Now let's add a configuration file for Supervisor. The default file is called
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+``supervisord.conf`` and is located in ``/etc/supervisor/conf.d/``.
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+
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+.. code-block:: bash
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+
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+ ADD supervisord.conf /etc/supervisor/conf.d/supervisord.conf
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+
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+Let's see what is inside our ``supervisord.conf`` file.
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+
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+.. code-block:: bash
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+
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+ [supervisord]
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+ nodaemon=true
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+
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+ [program:sshd]
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+ command=/usr/sbin/sshd -D
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+
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+ [program:apache2]
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+ command=/bin/bash -c "source /etc/apache2/envvars && /usr/sbin/apache2 -DFOREGROUND"
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+
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+The ``supervisord.conf`` configuration file contains directives that configure
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+Supervisor and the processes it manages. The first block ``[supervisord]``
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+provides configuration for Supervisor itself. We're using one directive,
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+``nodaemon`` which tells Supervisor to run interactively rather than daemonize.
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+
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+The next two blocks manage the services we wish to control. Each block controls
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+a separate process. The blocks contain a single directive, ``command``, which
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+specifies what command to run to start each process.
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+
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+Exposing ports and running Supervisor
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+-------------------------------------
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+
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+Now let's finish our ``Dockerfile`` by exposing some required ports and
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+specifying the ``CMD`` instruction to start Supervisor when our container
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+launches.
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+
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+.. code-block:: bash
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+
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+ EXPOSE 22 80
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+ CMD ["/usr/bin/supervisord"]
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+
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+Here we've exposed ports 22 and 80 on the container and we're running the
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+``/usr/bin/supervisord`` binary when the container launches.
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+
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+Building our container
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+----------------------
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+
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+We can now build our new container.
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+
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+.. code-block:: bash
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+
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+ sudo docker build -t <yourname>/supervisord .
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+
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+Running our Supervisor container
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+--------------------------------
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+
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+Once we've got a built image we can launch a container from it.
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+
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+.. code-block:: bash
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+
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+ sudo docker run -p 22 -p 80 -t -i <yourname>/supervisor
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+ 2013-11-25 18:53:22,312 CRIT Supervisor running as root (no user in config file)
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+ 2013-11-25 18:53:22,312 WARN Included extra file "/etc/supervisor/conf.d/supervisord.conf" during parsing
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+ 2013-11-25 18:53:22,342 INFO supervisord started with pid 1
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+ 2013-11-25 18:53:23,346 INFO spawned: 'sshd' with pid 6
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+ 2013-11-25 18:53:23,349 INFO spawned: 'apache2' with pid 7
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+ . . .
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+
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+We've launched a new container interactively using the ``docker run`` command.
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+That container has run Supervisor and launched the SSH and Apache daemons with
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+it. We've specified the ``-p`` flag to expose ports 22 and 80. From here we can
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+now identify the exposed ports and connect to one or both of the SSH and Apache
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+daemons.
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+
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