Merge pull request #12614 from ankushagarwal/ubuntu-docs

Add Configuring Docker article

docs/mkdocs.yml

@@ -109,6 +109,7 @@ pages:
 - ['articles/dockerfile_best-practices.md', 'Articles', 'Best practices for writing Dockerfiles']
 - ['articles/certificates.md', 'Articles', 'Using certificates for repository client verification']
 - ['articles/using_supervisord.md', 'Articles', 'Using Supervisor']
+- ['articles/configuring.md', 'Articles', 'Configuring Docker']
 - ['articles/cfengine_process_management.md', 'Articles', 'Process management with CFEngine']
 - ['articles/puppet.md', 'Articles', 'Using Puppet']
 - ['articles/chef.md', 'Articles', 'Using Chef']

docs/sources/articles/configuring.md

@@ -0,0 +1,98 @@
+page_title: Configuring Docker
+page_description: Configuring the Docker daemon on various distributions
+page_keywords: docker, daemon, configuration
+
+# Configuring Docker on various distributions
+
+After successfully installing Docker, the `docker` daemon runs with it's default
+configuration. You can configure the `docker` daemon by passing configuration
+flags to it directly when you start it.  
+
+In a production environment, system administrators typically configure the
+`docker` daemon to start and stop according to an organization's requirements.  In most
+cases, the system administrator configures a process manager such as `SysVinit`, `Upstart`,
+or `systemd` to manage the `docker` daemon's start and stop.
+
+Some of the daemon's options are:
+
+| Flag                  | Description                                               |
+|-----------------------|-----------------------------------------------------------|
+| `-D`, `--debug=false` | Enable or disable debug mode.  By default, this is false. |
+| `-H`,`--host=[]`      | Daemon socket(s) to connect to.                           |
+| `--tls=false`         | Enable or disable TLS. By default, this is false.         |
+
+The command line reference has the [complete list of daemon flags](/reference/commandline/cli/#daemon).
+
+## Direct Configuration
+
+If you're running the `docker` daemon directly by running `docker -d` instead of using a process manager,
+you can append the config options to the run command directly.
+
+
+Here is a an example of running the `docker` daemon with config options:
+
+    docker -d -D --tls=false -H tcp://0.0.0.0:2375
+
+These options : 
+
+- Enable `-D` (debug) mode 
+- Set `tls` to false
+- Listen for connections on `tcp://0.0.0.0:2375`
+
+
+## Ubuntu
+
+After successfully [installing Docker for Ubuntu](/installation/ubuntulinux/), you can check the
+running status using Upstart in this way:
+
+    $ sudo status docker
+    docker start/running, process 989
+
+You can start/stop/restart `docker` using
+
+    $ sudo start docker
+
+    $ sudo stop docker
+
+    $ sudo restart docker
+
+
+### Configuring Docker
+
+You configure the `docker` daemon in the `/etc/default/docker` file on your
+system.  You do this by specifying values in a `DOCKER_OPTS` variable. 
+To configure Docker options:
+
+1. Log into your system as a user with `sudo` or `root` privileges.
+
+2. If you don't have one, create the `/etc/default/docker` file in your system. 
+
+	Depending on how you installed Docker, you may already have this file.
+
+3. Open the file with your favorite editor.
+
+		$ sudo vi /etc/default/docker
+		
+4. Add a `DOCKER_OPTS` variable with the following options. These options are appended to the
+`docker` daemon's run command.
+
+	``` 
+	 DOCKER_OPTS=" --dns 8.8.8.8 --dns 8.8.4.4 -D --tls=false -H tcp://0.0.0.0:2375 "
+	```
+	
+These options : 
+
+- Set `dns` server for all containers
+- Enable `-D` (debug) mode 
+- Set `tls` to false
+- Listen for connections on `tcp://0.0.0.0:2375`
+  
+5. Save and close the file.
+
+6. Restart the `docker` daemon.
+
+ 		 $ sudo restart docker
+
+7. Verify that the `docker` daemon is running as specified wit the `ps` command.
+
+		$ ps aux | grep docker | grep -v grep