Recommendations for when to use virtual-based backup and agent-based backup

Last published : Apr 02, 2026
Backup Exec offers two backup methods for virtual machines: virtual-based backup and agent-based backup.
Virtual-based backup
  • Traditional
In the traditional method, all full, incremental, and differential backups are taken from the source virtual machine.
  • Forever Incremental
In Forever Incremental backups a full backup is taken from the source virtual machine and then followed by incremental backups. A consolidate backup is run by consolidating the previous set of full and incremental backups. Subsequent incremental backups use the consolidate full backup as a baseline to determine changes in the source virtual machine. A consolidate full backup is equivalent to a full backup from the source virtual machine. If you select deduplication disk storage for forever incremental backups, the Backup Exec Deduplication Block Cloning technology is used that significantly improves backup performance.
See Differences between the traditional and the forever incremental backups of virtual machines.
See About Forever Incremental Backup.
A virtual-based backup requires the Agent for VMware and Hyper-V to be installed on the Backup Exec server. For Hyper-V environments, the Agent for VMware and Hyper-V must also be installed on the Hyper-V host. In addition, the virtual machine's host or the vCenter Server must be added to Backup Exec as a server. This backup method uses VMware VADP APIs or Microsoft VSS snapshots to protect virtual machines.
Virtual-based backup is recommended for the following:
  • Backups that require file/folder-level Granular Recovery Technology (GRT)
    Note: The Agent for Windows must be installed on the virtual machine to restore file/folder-level GRT items back to their original location.
  • Single-server, application-level GRT for Active Directory, Exchange, SQL, and SharePoint.
    Note: The Agent for Windows must be installed on the virtual machine to perform application-level GRT.
  • Backups that do not require GRT
  • Offline virtual machines
  • Disaster recovery
  • Virtual machine templates.
Virtual-based backup is not recommended for the following:
  • Backups of Oracle, Enterprise Vault, distributed SharePoint farms, and Exchange DAG. Virtual-based backup does not support application-level GRT for those items.
Agent-based backup
An agent-based backup requires the Agent for Windows to be installed on the guest virtual machine. This backup method is sometimes referred to as legacy backup, traditional backup, or in-guest backup. With this backup method, a virtual machine is treated as a physical server.
Agent-based backup is recommended for the following:
  • Exchange DAG
  • Oracle
  • Enterprise Vault
  • Distributed SharePoint farm
  • A subset of files on the virtual machine (no system state)
  • VMware Fault Tolerant virtual machines
  • Virtual machines with Physical Raw Device Mapping (RDMS)
Agent-based backup is not recommended for the following:
  • Disaster recovery of a virtual machine.
  • Offline virtual machines
  • Virtual machine templates