| :title: Running a Riak service |
| :description: Build a Docker image with Riak pre-installed |
| :keywords: docker, example, package installation, networking, riak |
| |
| Riak Service |
| ============================== |
| |
| .. include:: example_header.inc |
| |
| The goal of this example is to show you how to build a Docker image with Riak |
| pre-installed. |
| |
| Creating a ``Dockerfile`` |
| +++++++++++++++++++++++++ |
| |
| Create an empty file called ``Dockerfile``: |
| |
| .. code-block:: bash |
| |
| touch Dockerfile |
| |
| Next, define the parent image you want to use to build your image on top of. |
| We’ll use `Ubuntu <https://index.docker.io/_/ubuntu/>`_ (tag: ``latest``), |
| which is available on the `docker index <http://index.docker.io>`_: |
| |
| .. code-block:: bash |
| |
| # Riak |
| # |
| # VERSION 0.1.0 |
| |
| # Use the Ubuntu base image provided by dotCloud |
| FROM ubuntu:latest |
| MAINTAINER Hector Castro hector@basho.com |
| |
| Next, we update the APT cache and apply any updates: |
| |
| .. code-block:: bash |
| |
| # Update the APT cache |
| RUN sed -i.bak 's/main$/main universe/' /etc/apt/sources.list |
| RUN apt-get update |
| RUN apt-get upgrade -y |
| |
| After that, we install and setup a few dependencies: |
| |
| - ``curl`` is used to download Basho's APT repository key |
| - ``lsb-release`` helps us derive the Ubuntu release codename |
| - ``openssh-server`` allows us to login to containers remotely and join Riak |
| nodes to form a cluster |
| - ``supervisor`` is used manage the OpenSSH and Riak processes |
| |
| .. code-block:: bash |
| |
| # Install and setup project dependencies |
| RUN apt-get install -y curl lsb-release supervisor openssh-server |
| |
| RUN mkdir -p /var/run/sshd |
| RUN mkdir -p /var/log/supervisor |
| |
| RUN locale-gen en_US en_US.UTF-8 |
| |
| ADD supervisord.conf /etc/supervisor/conf.d/supervisord.conf |
| |
| RUN echo 'root:basho' | chpasswd |
| |
| Next, we add Basho's APT repository: |
| |
| .. code-block:: bash |
| |
| RUN curl -s http://apt.basho.com/gpg/basho.apt.key | apt-key add -- |
| RUN echo "deb http://apt.basho.com $(lsb_release -cs) main" > /etc/apt/sources.list.d/basho.list |
| RUN apt-get update |
| |
| After that, we install Riak and alter a few defaults: |
| |
| .. code-block:: bash |
| |
| # Install Riak and prepare it to run |
| RUN apt-get install -y riak |
| RUN sed -i.bak 's/127.0.0.1/0.0.0.0/' /etc/riak/app.config |
| RUN echo "ulimit -n 4096" >> /etc/default/riak |
| |
| Almost there. Next, we add a hack to get us by the lack of ``initctl``: |
| |
| .. code-block:: bash |
| |
| # Hack for initctl |
| # See: https://github.com/dotcloud/docker/issues/1024 |
| RUN dpkg-divert --local --rename --add /sbin/initctl |
| RUN ln -s /bin/true /sbin/initctl |
| |
| Then, we expose the Riak Protocol Buffers and HTTP interfaces, along with SSH: |
| |
| .. code-block:: bash |
| |
| # Expose Riak Protocol Buffers and HTTP interfaces, along with SSH |
| EXPOSE 8087 8098 22 |
| |
| Finally, run ``supervisord`` so that Riak and OpenSSH are started: |
| |
| .. code-block:: bash |
| |
| CMD ["/usr/bin/supervisord"] |
| |
| Create a ``supervisord`` configuration file |
| +++++++++++++++++++++++++++++++++++++++++++ |
| |
| Create an empty file called ``supervisord.conf``. Make sure it's at the same |
| directory level as your ``Dockerfile``: |
| |
| .. code-block:: bash |
| |
| touch supervisord.conf |
| |
| Populate it with the following program definitions: |
| |
| .. code-block:: bash |
| |
| [supervisord] |
| nodaemon=true |
| |
| [program:sshd] |
| command=/usr/sbin/sshd -D |
| stdout_logfile=/var/log/supervisor/%(program_name)s.log |
| stderr_logfile=/var/log/supervisor/%(program_name)s.log |
| autorestart=true |
| |
| [program:riak] |
| command=bash -c ". /etc/default/riak && /usr/sbin/riak console" |
| pidfile=/var/log/riak/riak.pid |
| stdout_logfile=/var/log/supervisor/%(program_name)s.log |
| stderr_logfile=/var/log/supervisor/%(program_name)s.log |
| |
| Build the Docker image for Riak |
| +++++++++++++++++++++++++++++++ |
| |
| Now you should be able to build a Docker image for Riak: |
| |
| .. code-block:: bash |
| |
| docker build -t "<yourname>/riak" . |
| |
| Next steps |
| ++++++++++ |
| |
| Riak is a distributed database. Many production deployments consist of `at |
| least five nodes <http://basho.com/why-your-riak-cluster-should-have-at-least- |
| five-nodes/>`_. See the `docker-riak <https://github.com/hectcastro /docker- |
| riak>`_ project details on how to deploy a Riak cluster using Docker and |
| Pipework. |