AWS-EC2-Manage-Snapshots-Backup is a project mainly written in PHP, it's free.
This project is intended to give a simple script to AWS owners to do volume's backup with retention
This is a simple script based upon AWS SDK PHP to manage volume's snapshots.
It simply create one snapshot per volume (once you run it) and delete snapshot older then 1 month.
Please provide you personal information by copying config-sample.inc.php into config.inc.php.
Run the script backup-snapshots.php with your CRON.
For example:
00 08 /usr/bin/php /var/virtual/aws/backup-snapshots.php 00 22 /usr/bin/php /var/virtual/aws/backup-snapshots.php 00 12 7 /usr/bin/php /var/virtual/aws/backup-snapshots.php