AWS CloudFormation template that deploys an EC2-based approach to automating snapshots of EBS volumes

Why?

There are many solutions to this problem availble on the Internet. Most leverage AWS Lambda, and that is a great approach. Unfortunately, a customer I support is not yet comfortable with Lambda, so that service is not approved for use (yet). I needed to get creative, so I developed an different approach.

Features

• Snapshots are performed on a fixed schedule (configurable)
• Snapshots are retained for a set number of days (configurable)
• Snapshots are automatically deleted once expired
• Auto Scaling Group spans all Availability Zones in the given AWS region to achieve high availability
• Auto Scaling Group provides self-healing capabilities to ensure a running instance at all times
• Launch Configuration fully bootstraps new instances (assumes CentOS 7 base AMI)
• CloudFormation stack provisions requisite IAM resources

Prerequisites

• AWS account
• IAM user with sufficient privileges + access key
• Create a key pair in the desired AWS region
• Create a Security Group for your EC2 instance
• Find the ID of a trusted CentOS 7 base AMI in the target AWS region
  • The provided EC2 bootstrap script (UserData) assumes CentOS 7
• If you intend to use the provided helper scripts (see below), you will also need to:
  • Install the AWS CLI
  • Run aws configure to set the desired region, access key, and secret access key

Usage

Three helper script templates are provided. Drop the .template suffix from each and make the appropriate edits for your environment and configuration.

• validate-template.sh
  • helper script to validate the CloudFormation template
  • useful if you make modifications to the template
  • be sure to substitute the appropriate values for the profile and region options
• create-stack.sh
  • helper script to create the CloudFormation stack
  • be sure to substitute the appropriate values for the profile, region, and stack-name options
  • be sure to pass in appropriate values for the SshKey, SecurityGroupId, CentOS7AmiId, InstanceType, SnapshotRetentionDays, and EbsBackupCronExpression parameters
• delete-stack.sh
  • helper script to delete the CloudFormation stack and cleanup all resources that were created