Application-consistent backups on vSphere VMs

While protecting the entire file system of a Windows VM, the VRA can create application-consistent backups of Microsoft SQL Server, Exchange, SharePoint and Active Directory on the VM.

Note: A VRA backup is not sufficient for an authoritative restore of Active Directory objects. For an authoritative restore, a System State backup with the Windows Agent is required.

In an application-consistent backup, pending application transactions are written to disk before the data is backed up. This minimizes the amount of work required to restore the application.

If you enable application-consistent backups in a backup job but an application-consistent backup cannot be created for a VM, the VRA creates a crash-consistent backup for the VM. To check whether each VM backup is application-consistent or crash-consistent, view the backup log.

Application-consistent backups are only supported on Windows VMs. If Linux VMs are included in backup jobs where the application-consistent backup setting is enabled, warning messages for the Linux VMs may appear in the backup logs.

To create an application-consistent backup on a VM, VMware Tools version 11 or later must be installed on the VM.

Note: The VRA cannot create application-consistent backups on encrypted VMs. VMware does not support application-quiesced snapshots for encrypted VMs.

Note: The VRA cannot back up or restore an application database on a physical Raw Device Mapping (pRDM), shared or independent disk. VMware does not allow these disk types to be included in snapshots for VM-level backups. To back up an application on a pRDM, shared or independent disk, install the Windows Agent and SQL Server or Exchange Plug-in on the VM.

Log truncation in application-consistent backups

When performing application-consistent backups, the vSphere Recovery Agent can truncate SQL Server, Exchange and SharePoint transaction logs on VMs. This prevents the transaction logs from taking up a significant amount of disk space and reducing system performance. There are no logs to truncate when performing application-consistent backups of domain controllers with Active Directory.

Note: The vSphere Recovery Agent can truncate transaction logs for the default SQL Server instance and for all Exchange Server databases. The VRA cannot truncate logs for named SQL Server instances.

To truncate transaction logs on a VM after an application-consistent backup, you must enable log truncation in the backup job and provide credentials that have admin access to the VM. The specified user does not need admin rights to applications on the VM; it only needs admin access to the VM.

You can provide guest VM credentials with admin access to multiple VMs in a backup job and/or provide credentials for specific VMs. If you provide credentials for a specific VM, the guest VM credentials for multiple VMs will never be used to connect to that VM.

Logs cannot be truncated if an application-consistent backup could not be performed for some reason (e.g., VMware tools not installed on the guest VM).

To check whether log truncation was successful on each VM after a backup, view the backup logs.

Note: If you also back up databases using another tool (e.g., native SQL Server backup), use only one tool for truncating logs.