If you're taking offsite backups over the WAN / VPN / Fiber connections or even running Replication and especially going over a slow connection, you might be looking to throttle the bandwidth available for the offsite backups via Altaro VM Backup.

Altaro VM Backup does not offer throttling natively as it stands, but fortunately Windows gives you the functionality to do this built-in.

All you have to do is open PowerShell and run the following command on the Altaro machine and ALL Hyper-V Hosts:

Syntax for Offsite Backups:

New-NetQosPolicy "AOS Throttle" -IPDstPortStartMatchCondition 35116 -IPDstPortEndMatchCondition 35117 -ThrottleRateActionBitsPerSecond 10000000

Syntax for Replication:

New-NetQosPolicy "AOS Replication Throttle" -IPDstPortMatchCondition 35120 -ThrottleRateActionBitsPerSecond 10000000

The ThrottleRateActionBitsPerSecond must be specified in bits. So for instance;

  • 3 Mbps = 3000000 Bits
  • 10 Mbps = 10000000 Bits


  • For VMware hosts, this only needs to be applied on the machine running Altaro.
  • To throttle offsite backups for Azure / Amazon S3 / Wasabi Cloud Storage, please contact the Altaro support team.

If you wish to remove the QoS Policies, you can run the following commands:

Remove-NetQosPolicy -Name "AOS Throttle"

Remove-NetQosPolicy -Name "AOS Replication Throttle"