Help Center
Choose product document...
Veeam Backup & Replication 9.5
User Guide for Microsoft Hyper-V

Application-Aware Processing

To create transactionally consistent backups or replicas of VMs that run VSS-aware applications such as Microsoft Active Directory, Microsoft SQL Server, Microsoft SharePoint, Microsoft Exchange or Oracle, you must enable application-aware processing for the job.

Application-aware processing is Veeam's proprietary technology based on Microsoft VSS. Microsoft VSS is responsible for quiescing applications on the VM and creating a consistent view of application data on the VM guest OS. Use of Microsoft VSS ensures that there are no unfinished database transactions or incomplete application files when Veeam Backup & Replication triggers the VM checkpoint and starts copying VM data to the target. For more information about Microsoft VSS, see

Application-aware processing for Microsoft Windows Server versions is supported by corresponding versions of Microsoft Hyper-V ( To use application-aware processing, you must have Hyper-V Integration Services and the latest updates installed on the VM guest OS.

Application-Aware Processing Important!

If a VM runs an application that does not support Microsoft VSS (there is no VSS writer for this particular type of application, for example, MySQL), Veeam Backup & Replication will not be able to utilize Microsoft VSS and application-aware processing for this VM. To process such VMs, you can use Microsoft Hyper-V guest quiescence with pre-freeze and post-thaw scripts. For more information, see Microsoft Hyper-V Guest Quiescence and Pre-Freeze and Post-Thaw Scripts.

How Application-Aware Processing Works

If you enable application-aware processing for the job, Veeam Backup & Replication performs the following operations as a part of the backup or replication process:

  1. Veeam Backup & Replication deploys the runtime process on the VM and detects if the VM runs VSS-aware applications.
  2. Veeam Backup & Replication collects information about applications installed on VMs; this information is required for VSS-aware restore.
  3. Veeam Backup & Replication prepares applications for VSS-aware restore (VSS-aware restore is performed when the VM is started after you restore it from the backup or fail over to a VM replica).
  4. Microsoft VSS communicates with applications and quiesces I/O activities at a specific point in time.
  5. Microsoft Hyper-V VSS requestor triggers a VM VSS snapshot.
  6. Microsoft VSS resumes quiesced I/O activities on the VM guest OS.
  7. Veeam Backup & Replication triggers a snapshot for the volume on which the VM is located.
  8. The job session proceeds as usual.
  9. If you have instructed Veeam Backup & Replication to truncate transaction logs, Veeam Backup & Replication truncates transaction logs on the VM guest OS after the backup or replica are successfully created.

Application-Aware Processing 

Veeam Large Logo

User Guide for VMware vSphere

User Guide for Microsoft Hyper-V

Enterprise Manager User Guide

Veeam Cloud Connect Guide

Veeam Agent Management Guide

Veeam Backup Explorers User Guide

PowerShell Reference

RESTful API Reference

Veeam Backup FREE Edition User Guide

Veeam Backup for Microsoft Office 365 Documentation

Veeam ONE Documentation

Veeam Agent for Windows Documentation

Veeam Agent for Linux Documentation

Veeam Management Pack Documentation