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@@ -4,31 +4,51 @@ page_keywords: systemd, upstart, supervisor, docker, documentation, host integra
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# Automatically Start Containers
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-You can use your Docker containers with process managers like
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-`upstart`, `systemd` and `supervisor`.
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+As of Docker 1.2,
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+[restart policies](/reference/commandline/cli/#restart-policies) are the
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+built-in Docker mechanism for restarting containers when they exit. If set,
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+restart policies will be used when the Docker daemon starts up, as typically
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+happens after a system boot. Restart policies will ensure that linked containers
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+are started in the correct order.
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-## Introduction
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+If restart policies don't suit your needs (i.e., you have non-Docker processes
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+that depend on Docker containers), you can use a process manager like
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+[upstart](http://upstart.ubuntu.com/),
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+[systemd](http://freedesktop.org/wiki/Software/systemd/) or
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+[supervisor](http://supervisord.org/) instead.
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-If you want a process manager to manage your containers you will need to
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-run the docker daemon with the `-r=false` so that docker will not
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-automatically restart your containers when the host is restarted.
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+
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+## Using a Process Manager
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+
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+Docker does not set any restart policies by default, but be aware that they will
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+conflict with most process managers. So don't set restart policies if you are
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+using a process manager.
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+
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+*Note:* Prior to Docker 1.2, restarting of Docker containers had to be
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+explicitly disabled. Refer to the
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+[previous version](/v1.1/articles/host_integration/) of this article for the
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+details on how to do that.
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When you have finished setting up your image and are happy with your
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running container, you can then attach a process manager to manage it.
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-When you run `docker start -a` docker will automatically attach to the
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+When you run `docker start -a`, Docker will automatically attach to the
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running container, or start it if needed and forward all signals so that
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the process manager can detect when a container stops and correctly
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restart it.
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Here are a few sample scripts for systemd and upstart to integrate with
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-docker.
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+Docker.
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+
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-## Sample Upstart Script
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+## Examples
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-In this example We've already created a container to run Redis with
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-`--name redis_server`. To create an upstart script for our container, we
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-create a file named `/etc/init/redis.conf` and place the following into
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-it:
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+The examples below show configuration files for two popular process managers,
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+upstart and systemd. In these examples, we'll assume that we have already
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+created a container to run Redis with `--name=redis_server`. These files define
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+a new service that will be started after the docker daemon service has started.
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+
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+
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+### upstart
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description "Redis container"
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author "Me"
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@@ -39,12 +59,8 @@ it:
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/usr/bin/docker start -a redis_server
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end script
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-Next, we have to configure docker so that it's run with the option
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-`-r=false`. Run the following command:
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-
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- $ sudo sh -c "echo 'DOCKER_OPTS=\"-r=false\"' >> /etc/default/docker"
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-## Sample systemd Script
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+### systemd
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[Unit]
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Description=Redis container
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Andy Wilson