Crash-Consistent Backup

Crash-consistent backup is a proprietary Veeam method of creating crash-consistent VM images. A crash-consistent image can be compared to the state of a VM that has been manually reset. Unlike an offline backup, crash-consistent backup does not require any VM downtime.

Crash-consistent backup of VMs on Microsoft Hyper-V 2016 and later versions relies on standard checkpoints and works in the following way:

1. Veeam Backup & Replication requests a standard checkpoint of a specific VM.
2. Further activities depend on the backup mode:

• In on-host backup mode, Veeam Backup & Replication reads data from VM disks in read-only state. After the VM processing is complete, the standard checkpoint is merged with the original VM.
• In off-host backup mode, the Microsoft Hyper-V host VSS provider takes a snapshot of the volume on which VM disks are located.

The volume snapshot is mounted to the off-host backup proxy and presented to Veeam Backup & Replication. Veeam Backup & Replication reads VM data from the volume snapshot. After the backup job is complete, the volume snapshot and checkpoint are deleted.

Related Topics

• Online Backup
• On-Host Backup
• Off-Host Backup

• Creating Backup Jobs

• Creating Replication Jobs