github.com/ld86/docker@v1.7.1-rc3/docs/articles/using_supervisord.md (about) 1 <!--[metadata]> 2 +++ 3 title = "Using Supervisor with Docker" 4 description = "How to use Supervisor process management with Docker" 5 keywords = ["docker, supervisor, process management"] 6 [menu.main] 7 parent = "smn_third_party" 8 +++ 9 <![end-metadata]--> 10 11 # Using Supervisor with Docker 12 13 > **Note**: 14 > - **If you don't like sudo** then see [*Giving non-root 15 > access*](/installation/binaries/#giving-non-root-access) 16 17 Traditionally a Docker container runs a single process when it is 18 launched, for example an Apache daemon or a SSH server daemon. Often 19 though you want to run more than one process in a container. There are a 20 number of ways you can achieve this ranging from using a simple Bash 21 script as the value of your container's `CMD` instruction to installing 22 a process management tool. 23 24 In this example we're going to make use of the process management tool, 25 [Supervisor](http://supervisord.org/), to manage multiple processes in 26 our container. Using Supervisor allows us to better control, manage, and 27 restart the processes we want to run. To demonstrate this we're going to 28 install and manage both an SSH daemon and an Apache daemon. 29 30 ## Creating a Dockerfile 31 32 Let's start by creating a basic `Dockerfile` for our 33 new image. 34 35 FROM ubuntu:13.04 36 MAINTAINER examples@docker.com 37 38 ## Installing Supervisor 39 40 We can now install our SSH and Apache daemons as well as Supervisor in 41 our container. 42 43 RUN apt-get update && apt-get install -y openssh-server apache2 supervisor 44 RUN mkdir -p /var/lock/apache2 /var/run/apache2 /var/run/sshd /var/log/supervisor 45 46 Here we're installing the `openssh-server`, 47 `apache2` and `supervisor` 48 (which provides the Supervisor daemon) packages. We're also creating four 49 new directories that are needed to run our SSH daemon and Supervisor. 50 51 ## Adding Supervisor's configuration file 52 53 Now let's add a configuration file for Supervisor. The default file is 54 called `supervisord.conf` and is located in 55 `/etc/supervisor/conf.d/`. 56 57 COPY supervisord.conf /etc/supervisor/conf.d/supervisord.conf 58 59 Let's see what is inside our `supervisord.conf` 60 file. 61 62 [supervisord] 63 nodaemon=true 64 65 [program:sshd] 66 command=/usr/sbin/sshd -D 67 68 [program:apache2] 69 command=/bin/bash -c "source /etc/apache2/envvars && exec /usr/sbin/apache2 -DFOREGROUND" 70 71 The `supervisord.conf` configuration file contains 72 directives that configure Supervisor and the processes it manages. The 73 first block `[supervisord]` provides configuration 74 for Supervisor itself. We're using one directive, `nodaemon` 75 which tells Supervisor to run interactively rather than 76 daemonize. 77 78 The next two blocks manage the services we wish to control. Each block 79 controls a separate process. The blocks contain a single directive, 80 `command`, which specifies what command to run to 81 start each process. 82 83 ## Exposing ports and running Supervisor 84 85 Now let's finish our `Dockerfile` by exposing some 86 required ports and specifying the `CMD` instruction 87 to start Supervisor when our container launches. 88 89 EXPOSE 22 80 90 CMD ["/usr/bin/supervisord"] 91 92 Here We've exposed ports 22 and 80 on the container and we're running 93 the `/usr/bin/supervisord` binary when the container 94 launches. 95 96 ## Building our image 97 98 We can now build our new image. 99 100 $ docker build -t <yourname>/supervisord . 101 102 ## Running our Supervisor container 103 104 Once We've got a built image we can launch a container from it. 105 106 $ docker run -p 22 -p 80 -t -i <yourname>/supervisord 107 2013-11-25 18:53:22,312 CRIT Supervisor running as root (no user in config file) 108 2013-11-25 18:53:22,312 WARN Included extra file "/etc/supervisor/conf.d/supervisord.conf" during parsing 109 2013-11-25 18:53:22,342 INFO supervisord started with pid 1 110 2013-11-25 18:53:23,346 INFO spawned: 'sshd' with pid 6 111 2013-11-25 18:53:23,349 INFO spawned: 'apache2' with pid 7 112 . . . 113 114 We've launched a new container interactively using the `docker run` command. 115 That container has run Supervisor and launched the SSH and Apache daemons with 116 it. We've specified the `-p` flag to expose ports 22 and 80. From here we can 117 now identify the exposed ports and connect to one or both of the SSH and Apache 118 daemons.