Deploying a Rails Application to Elastic Beanstalk
You can use the Elastic Beanstalk Command Line Interface (EB CLI) and Git to deploy a Rails application to Elastic Beanstalk. This walkthrough shows you how. You'll also learn how to set up a Rails installation from scratch in case you don't already have a development environment and application.
Many of the technologies presented here are under active development. For the best results, use the same versions of each tool when possible. The versions used during the development of this tutorial are listed below.
For the typographic conventions used in this tutorial, see Document Conventions in the General Reference.
Creating environments with the EB CLI requires an existing
service role named
role is typically created the first time you create an environment in the Elastic Beanstalk console. If you
don&t have a service role, run through the environment creation wizard in the console or create
a new service role in AWS Identity and Access Management and grant Elastic Beanstalk permission to use it.
See Service Roles, Instance Profiles, and User Policies for details.
Rails Development Environment Setup
Read this section if you are setting up a Rails development environment from scratch. If you have a development environment configured with Rails, Git and a working app, you can skip this section.
Getting an Ubuntu EC2 Instance
The following instructions were developed and tested using an Amazon EC2 instance running Ubuntu 14.04. For instructions on configuring and connecting to an EC2 instance using the AWS Management Console, read the Getting Started section of the Amazon EC2 User Guide for Linux.
If you don't have access to the AWS Management Console or prefer to use the command line, check out the AWS CLI User Guide for instructions on installing the AWS CLI and using it to configure security groups, create a key pair, and launch instances with the same credentials that you will use with the EB CLI.
RVM, a popular version manager for Ruby, provides an option to install RVM, Ruby, and Rails with just a few commands:
gpg --keyserver hkp://keys.gnupg.net --recv-keys D39DC0E3$
curl -sSL https://get.rvm.io | bash -s stable --rails$
Install nodejs to allow the Rails server to run locally:
sudo apt-get install nodejs
For help installing rails on other operating systems, try http://installrails.com/.
Create a New Rails Project
rails new with the name of the application to create a new Rails
rails new rails-beanstalk
Rails creates a directory with the name specified, generates all of the files needed to run a sample project locally, and then runs bundler to install all of the dependencies (Gems) defined in the project's Gemfile.
Run the Project Locally
Test your Rails installation by running the default project locally.
cd rails-beanstalkrails-beanstalk $
rails server -d=> Booting WEBrick => Rails 4.2.0 application starting in development on http://localhost:3000 => Run `rails server -h` for more startup options rails-beanstalk $
curl http://localhost:3000<!DOCTYPE html> <html> <head> <title>Ruby on Rails: Welcome aboard</title> ...
Elastic Beanstalk precompiles Rails assets by default. For Ruby 2.1 container types, note the following:
The nginx web server is preconfigured to serve assets from the
The Puma application requires that you add
gem "puma"to your
bundle execto run correctly.
Install the EB CLI
In this section you'll install the EB CLI, a few dependencies, and Git.
Using Git or another form of revision control is recommended but also entirely optional when using the EB CLI. Any of the steps in this tutorial that use Git can be skipped.
Install Git, Python Development Libraries and Pip
This tutorial uses Git for revision control and Pip to manage the EB CLI installation. In your Ubuntu development environment, you can install all of them with the following sequence of commands:
sudo apt-get install git$
sudo apt-get install python-dev$
curl "https://bootstrap.pypa.io/get-pip.py" -o "get-pip.py"$
sudo python get-pip.py
Install Python 3.4, which includes pip.
Install the EB CLI
With Pip you can install the EB CLI with a single command:
Linux, OS X, or Unix
sudo pip install awsebcli
pip install awsebcli
Set Up Your Git Repository
If your Rails project is already in a local Git repository, continue to Configure the EB CLI.
First, initiate the repository. From within the Rails project directory, type
git initInitialized empty Git repository in /home/ubuntu/rails-beanstalk/.git/
Next, add all of the project's files to the staging area and commit the change.
git add .rails-beanstalk $
git commit -m "default rails project"56 files changed, 896 insertions(+) create mode 100644 .gitignore create mode 100644 Gemfile ...
Configure the EB CLI
With the Git repository configured and all necessary tools installed, configuring the EB
CLI project is as simple as running
eb init from within the project directory and
following the prompts.
eb initSelect a default region 1) us-east-1 : US East (N. Virginia) 2) us-west-1 : US West (N. California) 3) us-west-2 : US West (Oregon) ...
The following values work for this tutorial, but feel free to use values that make sense for your requirements. If you don't have access keys, see How Do I Get Security Credentials? in the AWS General Reference.
Eb Init Values
|Region||Enter (keep default)|
|AWS Access Key ID||Your access key|
|AWS Secret Access Key||Your secret key|
|Application Name||Enter (keep default)|
|Using Ruby?||y (yes)|
|Platform Version||Enter (keep default)|
|Set up SSH?||n (no)|
In addition to configuring the environment for deployment,
eb init sets up
some Git extensions and adds an entry to the
.gitignore file in the project
directory. Commit the change to
.gitignore before moving on.
git commit -am "updated .gitignore"
Deploy the Project
Next, you'll deploy the default Rails project to an Elastic Beanstalk environment.
eb create rails-beanstalk-envCreating application version archive "app-150219_215138". Uploading rails-beanstalk/app-150219_215138.zip to S3. This may take a while. Upload Complete. Environment details for: rails-beanstalk-env Application name: rails-beanstalk Region: us-west-2 Deployed Version: app-150219_215138 Environment ID: e-pi3immkys7 Platform: 64bit Amazon Linux 2014.09 v1.2.0 running Ruby 2.1 (Puma) Tier: WebServer-Standard CNAME: UNKNOWN Updated: 2015-02-19 21:51:40.686000+00:00 Printing Status: INFO: createEnvironment is starting. ...
With just one command, the EB CLI sets up all of the resources our application needs to run in AWS, including the following:
An Amazon S3 bucket to store environment data
A load balancer to distribute traffic to the web server(s)
A security group to allow incoming web traffic
An Auto Scaling group to adjust the number of servers in response to load changes
Amazon CloudWatch alarms that notify the Auto Scaling group when load is low or high
An Amazon EC2 instance hosting our application
When the process is complete, the EB CLI outputs the public DNS name of the application
eb open to open the website in the default browser. In our
Ubuntu environment the default browser is a text based browser called W3M.
eb openA really lowlevel plumbing error occured. Please contact your local Maytag(tm) repair man.
This is Puma's way of telling us that something went wrong. When an error like this
occurs, you can check out the logs using the
eb logs command.
eb logsINFO: requestEnvironmentInfo is starting. INFO: [Instance: i-8cdc6480] Successfully finished tailing 5 log(s) ================ i-8cdc6480 ================= ------------------------------------- /var/log/eb-version-deployment.log ------------------------------------- ...
The error you're looking for is in the web container log,
... ------------------------------------- /var/log/puma/puma.log ------------------------------------- === puma startup: 2014-12-15 18:37:51 +0000 === === puma startup: 2014-12-15 18:37:51 +0000 ===  + Gemfile in context: /var/app/current/Gemfile  - Worker 0 (pid: 1982) booted, phase: 0 2014-12-15 18:41:42 +0000: Rack app error: #<RuntimeError: Missing `secret_key_base` for 'production' environment, set this value in `config/secrets.yml`> /opt/rubies/ruby-2.1.4/lib/ruby/gems/2.1.0/gems/railties-4.1.8/lib/rails/application.rb:462:in `validate_secret_key_config!' /opt/rubies/ruby-2.1.4/lib/ruby/gems/2.1.0/gems/railties-4.1.8/lib/rails/application.rb:195:in `env_config' ...
To get the application working, you need to configure a few environment variables. First
is SECRET_KEY_BASE, which is referred to by
secrets.yml in the
config folder of our project.
This variable is used to create keys and should be a secret, as the name suggests. This is
why you don't want it stored in source control where other people might see it. Set this to
any value using
eb setenv SECRET_KEY_BASE=INFO: Environment update is starting. INFO: Updating environment rails-beanstalk-env's configuration settings. INFO: Successfully deployed new configuration to environment. INFO: Environment update completed successfully.
The EB CLI automatically restarts the web server whenever you update configuration or deploy new code. Try loading the site again.
eb openThe page you were looking for doesn't exist (404)
A 404 error may not look like much of an improvement, but it shows that the web container is working and couldn't find a route to the page you're looking for.
So what happened to the welcome page you saw earlier? In this case the environment variable you need is RACK_ENV. Right now it's set to production, suppressing the display of debug features as well as the Welcome to Rails page.
View the current value of all environment variables using the
eb printenvEnvironment Variables: AWS_SECRET_KEY = None RAILS_SKIP_ASSET_COMPILATION = false SECRET_KEY_BASE = 23098520lkjsdlkjfsdf RACK_ENV = production PARAM5 = None PARAM4 = None PARAM3 = None PARAM2 = None PARAM1 = None BUNDLE_WITHOUT = test:development RAILS_SKIP_MIGRATIONS = false AWS_ACCESS_KEY_ID = None
The proper way to fix this is to add content and routes to the project. For the moment, though, we just want to see our project working, so we'll set RACK_ENV to development.
eb setenv RACK_ENV=development
The next time you load the site it should succeed.
eb openRuby on Rails: Welcome aboard ...
Now that you know it works, you can set RACK_ENV back to production and see about adding that content.
eb setenv RACK_ENV=production
Update the Application
Now it's time to add some content to the front page to avoid the 404 error you saw in production mode.
First you'll use
rails generate to create a controller, route, and view for
your welcome page.
rails generate controller WelcomePage welcomecreate app/controllers/welcome_page_controller.rb route get 'welcome_page/welcome' invoke erb create app/views/welcome_page create app/views/welcome_page/welcome.html.erb ...
This gives you all you need to access the page at
Before you publish the changes, however, change the content in the view and add a route to
make this page appear at the top level of the site.
Use your favorite text editor to edit the content in
app/views/welcome_page/welcome.html.erb. Nano and Vim are popular
command line editors. For this example, you'll use
cat to simply overwrite the
content of the existing file.
cat > app/views/welcome_page/welcome.html.erb>
<p>This is the front page of my first Rails application on Elastic Beanstalk.</p>Ctrl+D
Finally, add the following route to
Rails.application.routes.draw do get 'welcome_page/welcome' root 'welcome_page#welcome' end
This tells Rails to route requests to the root of the website to the welcome page
controller's welcome method, which renders the content in the welcome view
welcome.html.erb). Now we're ready to commit the changes and update our
git add .rails-beanstalk $
git commit -m "welcome page controller, view and route"rails-beanstalk $
eb deployINFO: Environment update is starting. INFO: Deploying new version to instance(s). INFO: New application version was deployed to running EC2 instances. INFO: Environment update completed successfully.
The update process is fairly quick. Read the front page at the command line using Curl or
navigate to the type
eb open to open the site in a web browser to see the
eb openWelcome This is the front page of my first Rails application on Elastic Beanstalk.
Now you're ready to continue work on your Rails site. Whenever you have new commits to
eb deploy to update your environment.
If you no longer want to run your application, you can clean up by terminating your environment and deleting your application.
terminate command to terminate your environment and the
delete command to delete your application.
To terminate your environment and delete the application
From the directory where you created your local repository, type the following command:
This process may take a few minutes. Elastic Beanstalk displays a message once the environment has been successfully terminated.
If you attached an Amazon RDS DB instance to your environment, your Amazon RDS DB will be deleted, and you will lose your data. To save your data, create a snapshot before you delete the application. For instructions on how to create a snapshot, go to Creating a DB Snapshot in the Amazon Relational Database Service User Guide.
hesitate to terminate an environment to save on resources while you continue to develop your
site. You can always recreate your Beanstalk environment using