dokku/docs/docker-options.md

# Docker Options

```
docker-options <app>                             Display apps docker options for all phases
docker-options <app> <phase(s)>                  Display apps docker options for phase (comma-separated phase list)
docker-options:add <app> <phase(s)> OPTION       Add docker option to app for phase (comma-separated phase list)
docker-options:remove <app> <phase(s)> OPTION    Remove docker option from app for phase (comma-separated phase list)
```

Add some options (first, for the deployed/running app and second when executing `dokku run`):

```
dokku docker-options:add myapp deploy "-v /host/path:/container/path"
dokku docker-options:add myapp run "-v /another/container/path"
```

Check what we added

```shell
dokku docker-options myapp
# Deploy options:
#    -v /host/path:/container/path
# Run options:
#    -v /another/container/path
```

Remove an option

```shell
dokku docker-options:remove myapp run "--link container_name:alias"
```

### Note about `dokku` phases and `docker-options`

`dokku` deploys your application in multiple "phases" and the `docker-options` plugin allows you to pass arguments to the underlying docker container in the following 3 phases/containers:

- `build`: the container that executes the appropriate buildpack
- `deploy`: the container that executes your running/deployed application
- `run`: the container that executes any arbitrary command via `dokku run myapp`

## Advanced Usage (avoid if possible)

In your applications folder (`/home/dokku/app_name`) create a file called `DOCKER_OPTIONS_RUN` (or `DOCKER_OPTIONS_BUILD` or `DOCKER_OPTIONS_DEPLOY`).

Inside this file list one docker option per line. For example:

```shell
--link container_name:alias
-v /host/path:/container/path
-v /another/container/path
```

The above example will result in the following options being passed to docker during `dokku run`:

```shell
--link container_name:alias -v /host/path:/container/path -v /another/container/path
```

You may also include comments (lines beginning with a #) and blank lines in the DOCKER_OPTIONS file.

Move information on docker options can be found here: http://docs.docker.io/en/latest/reference/run/ .