Step 4. Specify Guest Processing Settings

In this article

    If you back up EC2 instances that are currently running, at the Guest Processing step of the wizard, you can configure guest processing settings. These settings allow you to specify what actions Veeam Backup for AWS will perform when communicating with the instance guest OS to create transactionally consistent backups.


    To create transactionally consistent backups, Veeam Backup for AWS uses the AWS Systems Manager (SSM) service. For more information on the service, see AWS Documentation.

    Particularly, you can specify the following guest processing settings:

    • Enable application-aware processing. For Windows EC2 instances running VSS-aware applications, you can enable application-aware processing to ensure that the applications will be able to recover successfully, without data loss.

    Application-aware processing is the Veeam technology based on Microsoft VSS. Microsoft VSS is responsible for quiescing applications on EC2 instances and creating a consistent view of application data. For more information on Microsoft VSS, see Microsoft Docs.

    • Enable guest scripting. For an EC2 instance running applications that do not support Microsoft VSS, you can instruct Veeam Backup for AWS to run custom scripts on the instance before and after the backup operation. For example, Veeam Backup for AWS can execute a pre-snapshot script on the instance to quiesce these applications. This will allow Veeam Backup for AWS to create a transactionally consistent snapshot while no write operations occur on the instance volumes. After the snapshot is created, a post-snapshot script can start the applications again.


    EC2 instances running Microsoft Windows OS must have the 443 network port opened to ensure proper communication of Veeam Backup for AWS and the instance guest OSes.