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Limitation on Number of VMs per Snapshot

By default, during Backup from Storage Snapshots Veeam Backup & Replication creates VMware vSphere snapshots for all VMs that reside on the same volume or LUN, and then triggers a storage snapshot for this volume or LUN. If the number of VMs on the volume or LUN is great, VM snapshot creation may take much time. To speed up the backup or replication process, you can limit the number of VMs per storage snapshot.

To limit the number of storage snapshots, you must enable the Limit processed VM count per storage snapshot to <N> option and specify the number of VMs per snapshot in the job settings.

With the limitation option enabled, Veeam Backup & Replication processes VMs in several cycles:

Veeam Backup & Replication divides VMs into several groups, as defined in the Limit processed VM count per storage snapshot to <N> option.
Veeam Backup & Replication triggers VMware vSphere snapshots for VMs in the first group.
Veeam Backup & Replication triggers a storage snapshot for the volume or LUN on which VMs are hosted.
Veeam Backup & Replication deletes VMware vSphere snapshots for VMs in the first group.
Veeam Backup & Replication copies data of VMs in the first group from the storage snapshot.
Veeam Backup & Replication removes the storage snapshot.
Steps 2-6 are repeated for every remaining group of VMs.

For example, you add to the job 15 VMs whose disks are hosted on the same volume and set the Limit processed VM count per storage snapshot to <N> option to 10. Veeam Backup & Replication will divide all VMs into 2 groups — a group of 10 VMs and group of 5 VMs. Veeam Backup & Replication will perform the data processing cycle for the first group of VMs. When VM data processing is over, Veeam Backup & Replication will start processing the second group of VMs.