Menu
AWS Elastic Beanstalk
Developer Guide (API Version 2010-12-01)

Deploying a High-Availability PHP Application with an External Amazon RDS Database to Elastic Beanstalk

This tutorial walks you through the process of launching an RDS DB instance external to AWS Elastic Beanstalk, and configuring a high-availability environment running a PHP application to connect to it. Running a DB instance external to Elastic Beanstalk decouples the database from the lifecycle of your environment, and lets you connect to the same database from multiple environments, swap out one database for another, or perform a blue/green deployment without affecting your database.

The tutorial uses a sample PHP application that utilizes a MySQL database to store user-provided text data. The sample application uses configuration files to configure PHP settings and to create a table in the database for the application to use. It also shows how to use a Composer file to install packages during deployment.

Prerequisites

Before you start, download the sample application source bundle from GitHub: eb-demo-php-simple-app-1.1.zip

The procedures in this tutorial for Amazon Relational Database Service (Amazon RDS) tasks assume that you are launching resources in a default VPC. All new accounts include a default VPC in each region. If you don't have a default VPC, the procedures will vary. See Using Elastic Beanstalk with Amazon RDS for instructions for EC2-Classic and custom VPC platforms.

Launch a DB Instance in Amazon RDS

To use an external database with an application running in Elastic Beanstalk, first launch a DB instance with Amazon RDS. When you launch an instance with Amazon RDS, it is completely independent of Elastic Beanstalk and your Elastic Beanstalk environments, and will not be terminated or monitored by Elastic Beanstalk.

Use the Amazon RDS console to launch a Multi-AZ MySQL DB instance. Choosing a Multi-AZ deployment ensures that your database will failover and continue to be available if the master DB instance goes out of service.

To launch an RDS DB instance in a default VPC

  1. Open the RDS management console.

  2. Choose Launch DB Instance.

  3. Choose a DB Engine and preset configuration.

  4. Under Instance Specifications, choose a DB Instance Class. For high availability, set Multi-AZ Deployment to Yes.

  5. Under Settings, type a DB Instance Identifier, Master Username, and Master Password and note the values that you entered for later.

  6. Choose Next.

  7. For Network and Security settings, choose the following:

    • VPCDefault VPC

    • Subnet Groupdefault

    • Publicly AccessibleNo

    • Availability Zone No Preference

    • VPC Security GroupsCreate new Security Group

  8. For Database Name, type ebdb, and verify the default settings for the remaining options. Note the values of the following options:

    • Database Name

    • Database Port

  9. Choose Launch DB Instance.

Next, modify the security group attached to your DB instance to allow inbound traffic on the appropriate port. This is the same security group that you will attach to your Elastic Beanstalk environment later, so the rule that you add will grant ingress permission to other resources in the same security group.

To modify the ingress rules on your RDS instance's security group

  1. Open the Amazon RDS console.

  2. Choose Instances.

  3. Choose the arrow next to the entry for your DB instance to expand the view.

  4. Choose the Details tab.

  5. In the Security and Network section, the security group associated with the DB instance is shown. Open the link to view the security group in the Amazon EC2 console.

    Note

    Also note the Endpoint shown on this page for use later.

  6. In the security group details, choose the Inbound tab.

  7. Choose Edit.

  8. Choose Add Rule.

  9. For Type, choose the DB engine that your application uses.

  10. For Source, choose Custom, and then type the group ID of the security group. This allows resources in the security group to receive traffic on the database port from other resources in the same group.

  11. Choose Save.

Creating a DB instance takes about 10 minutes. In the meantime, launch your Elastic Beanstalk environment.

Launch an Elastic Beanstalk Environment

Use the AWS Management Console to launch an Elastic Beanstalk environment. Choose the PHP 5.6 platform configuration and accept the default settings and sample code. After you have configured the environment to connect to the database, you deploy the sample application that you downloaded from GitHub.

To launch an environment (console)

  1. Open the Elastic Beanstalk console with this preconfigured link: console.aws.amazon.com/elasticbeanstalk/home#/newApplication?applicationName=tutorials&environmentType=LoadBalanced

  2. For Platform, choose the platform that matches the language used by your application.

  3. For App code, choose Sample application.

  4. Choose Review and launch.

  5. Review all options and once you are satisfied with those options choose Create app.

Environment creation takes about 5 minutes.

Configure Security Groups, Environment Properties, and Scaling

Next, add the DB instance's security group to your running environment. This procedure causes Elastic Beanstalk to reprovision all instances in your environment with the additional security group attached.

To add a security group to your environment

  1. Open the Elastic Beanstalk console.

  2. Navigate to the management page for your environment.

  3. Choose Configuration.

  4. Choose Instances settings icon ( Edit).

  5. For EC2 security groups, type a comma after the name of the auto-generated security group followed by the name of the RDS DB instance's security group. By default, the RDS console creates a security group called rds-launch-wizard.

  6. Choose Apply.

  7. Read the warning, and then choose Save.

Next, pass the connection information to your environment by using environment properties. The sample application uses a default set of properties that match the ones that Elastic Beanstalk configures when you provision a database within your environment.

To configure environment properties for an Amazon RDS DB instance

  1. Open the Elastic Beanstalk console.

  2. Navigate to the management page for your environment.

  3. Choose Configuration.

  4. In the Software Configuration section, choose Edit.

  5. In the Environment Properties section, define the variables that your application reads to construct a connection string. For compatibility with environments that have an integrated RDS DB instance, use the following:

    • RDS_HOSTNAME – The hostname of the DB instance.

      Amazon RDS console label – Endpoint combines hostname and port.

    • RDS_PORT – The port on which the DB instance accepts connections. The default value varies between DB engines.

      Amazon RDS console label – Port

    • RDS_DB_NAME – The database name, ebdb.

      Amazon RDS console label – DB Name

    • RDS_USERNAME – The username that you configured for your database.

      Amazon RDS console label – Username

    • RDS_PASSWORD – The password that you configured for your database.

    Choose the plus symbol (+) to add additional properties:

  6. Choose Apply.

Finally, configure your environment's Auto Scaling group with a higher minimum instance count. Run at least two instances at all times to prevent the web servers in your environment from being a single point of failure, and to allow you to deploy changes without taking your site out of service.

To configure your environment's Auto Scaling group for high availability

  1. Open the Elastic Beanstalk console.

  2. Navigate to the management page for your environment.

  3. Choose Configuration.

  4. Choose Scaling.

  5. Under Auto Scaling, set Minimum instance count to 2 and the Maximum instance count to a value higher than 2.

  6. Choose Apply.

Deploy the Sample Application

Now your environment is ready to run the sample application and connect to Amazon RDS. Deploy the sample application to your environment.

Note

Download the source bundle from GitHub if you haven't already: eb-demo-php-simple-app-1.1.zip

To deploy a source bundle

  1. Open the Elastic Beanstalk console.

  2. Navigate to the management page for your environment.

  3. Choose Upload and Deploy.

  4. Choose Browse and upload the source bundle.

  5. Choose Deploy.

  6. When the deployment completes, choose the site URL to open your website in a new tab.

The site collects user comments and uses a MySQL database to store the data. To add a comment, choose Share Your Thought, enter a comment, and then choose Submit Your Thought. The web app writes the comment to the database so that it can be read by any instance in the environment and won't be lost if instances go out of service.

Launching an environment creates the following resources:

  • EC2 instance – An Amazon Elastic Compute Cloud (Amazon EC2) virtual machine configured to run web apps on the platform that you choose.

    Each platform runs a different set of software, configuration files, and scripts to support a specific language version, framework, web container, or combination thereof. Most platforms use either Apache or nginx as a reverse proxy that sits in front of your web app, forwards requests to it, serves static assets, and generates access and error logs.

  • Instance security group – An Amazon EC2 security group configured to allow ingress on port 80. This resource lets HTTP traffic from the load balancer reach the EC2 instance running your web app. By default, traffic is not allowed on other ports.

  • Load balancer – An Elastic Load Balancing load balancer configured to distribute requests to the instances running your application. A load balancer also eliminates the need to expose your instances directly to the Internet.

  • Load balancer security group – An Amazon EC2 security group configured to allow ingress on port 80. This resource lets HTTP traffic from the Internet reach the load balancer. By default, traffic is not allowed on other ports.

  • Auto Scaling group – An Auto Scaling group configured to replace an instance if it is terminated or becomes unavailable.

  • Amazon S3 bucket – A storage location for your source code, logs, and other artifacts that are created when you use Elastic Beanstalk.

  • Amazon CloudWatch alarms – Two Amazon CloudWatch alarms that monitor the load on the instances in your environment and are triggered if the load is too high or too low. When an alarm is triggered, your Auto Scaling group scales up or down in response.

  • AWS CloudFormation stack – Elastic Beanstalk uses AWS CloudFormation to launch the resources in your environment and propagate configuration changes. The resources are defined in a template that you can view in the AWS CloudFormation management console.

  • Domain name – A domain name that routes to your web app in the form subdomain.region.elasticbeanstalk.com.

All of these resources are managed by Elastic Beanstalk. When you terminate your environment, Elastic Beanstalk terminates all of resources that it contains. The RDS DB instance that you launched is outside of your environment, so you are responsible for managing its lifecycle.

Note

The S3 bucket that Elastic Beanstalk creates is shared between environments and is not deleted during environment termination. For more information, see Using Elastic Beanstalk with Amazon S3.

Clean Up

If you are done working with Elastic Beanstalk, you can terminate your PHP environment.

To terminate your Elastic Beanstalk environment

  1. Open the Elastic Beanstalk console.

  2. Navigate to the management page for your environment.

  3. Choose Actions, and then choose Terminate Environment.

Elastic Beanstalk terminates all AWS resources associated with your environment, including EC2 instances, the load balancer, security groups, Amazon CloudWatch alarms, etc.

You can also terminate the DB instance, taking a snapshot so that you can restore the data to another instance later.

To terminate your RDS DB instance

  1. Open the Amazon RDS console.

  2. Choose Instances.

  3. Choose your DB instance.

  4. Choose Instance Actions, and then choose Delete.

  5. Choose whether to create a snapshot, and then choose Delete.

Next Steps

As you continue to develop your application, you'll probably want to manage environments and deploy your application without manually creating a .zip file and uploading it to the Elastic Beanstalk console. The Elastic Beanstalk Command Line Interface (EB CLI) provides easy-to-use commands for creating, configuring, and deploying applications to Elastic Beanstalk environments from the command line.

The sample application uses configuration files to configure PHP settings and create a table in the database if it doesn't already exist. You can also use a configuration file to configure your instances' security group settings during environment creation to avoid time-consuming configuration updates. See Advanced Environment Customization with Configuration Files (.ebextensions) for more information.

For development and testing, you might want to use Elastic Beanstalk's functionality for adding a managed DB instance directly to your environment. For instructions on setting up a database inside your environment, see Configuring Databases with Elastic Beanstalk.

If you need a high-performance database, consider using Amazon Aurora. Amazon Aurora is a MySQL-compatible database engine that offers commercial database features at low cost. To connect your application to a different database, repeat the security group configuration steps and update the RDS-related environment properties.

Finally, if you plan on using your application in a production environment, configure a custom domain name for your environment and enable HTTPS for secure connections.