Beanstalk Configuration

Elastic Beanstalk provides options for

• customizing the resources in environment
• Elastic Beanstalk behavior
• platform settings.

EC2 instance

• set of software
• configuration files
• scripts to support a specific language version
• framework if applicable

Instance security group

• inbound traffic configuration
• lets traffic from load balancer reach EC2 instance

Load balancer

• configured to distribute requests
• requests to instances running application.
• Does not expose instances to internet

Load balancer security group

• An EC2 security group
• configured to allow inbound traffic
• It lets traffic reach the load balancer
• By default, traffic not allowed on other ports.

Auto Scaling group

• configured to replace an instance if
  • it is terminated
  • becomes unavailable.

Amazon S3 bucket

• A storage location created using Elastic Beanstalk and for
  • source code
  • logs
  • other artifacts

CloudWatch alarms

• Two CloudWatch alarms monitor load on instances in environment are triggered if the load
  • is too high or
  • too low
• After alarm trigger, Auto Scaling group scales up or down in response.

AWS CloudFormation stack

• Elastic Beanstalk uses CloudFormation
• launches resources in environment
• proliferate configuration changes.
• resources are defined template viewable in CloudFormation console.

Domain name

• It routes web application
• Has the form subdomain.region.elasticbeanstalk.com.

ebextensions

• they are Elastic Beanstalk configuration files
• can add them to application’s source code
• used to configure environment
• can also customize AWS resources
• They are YAMLor JSON-formatted documents
• Have a .config file extension
• deploy in application source bundle.

YAML vs JSON

• YAML is more readable than JSON.
• YAML supports
  • Comments
  • multi-line commands
  • several alternatives for using quotes

configuration file sections

• option_settings – defines values for configuration options.
• Resources section – further customize resources in application’s environment
• other sections of a configuration file  
  • packages
  • sources
  • files
  • users
  • groups
  • commands
  • container_commands

Config file Requirements

• Location – All configuration files be placed in one folder, named .ebextensions, in root of source bundle.
• Naming – must have the .config file extension.
• Formatting –must conform to YAML or JSON specifications.
• Uniqueness – Use each key once in file.