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 going to an Altaro Offsite Server:

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

Syntax for Offsite Backups going to a Cloud Backup Location:

New-NetQosPolicy "Cloud Backup Throttle Port 80" -IPPort 80 -IPProtocol TCP -ThrottleRateActionBitsPerSecond 10000000 -AppPathNameMatchCondition 'C:\Program Files\Altaro\Altaro Backup\Altaro.Services.BackupAgent.exe'

New-NetQosPolicy "Cloud Backup Throttle Port 443" -IPPort 443 -IPProtocol TCP -ThrottleRateActionBitsPerSecond 10000000 -AppPathNameMatchCondition 'C:\Program Files\Altaro\Altaro Backup\Altaro.Services.BackupAgent.exe'

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

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

Remove-NetQosPolicy -Name "AOS Throttle"
Remove-NetQosPolicy -Name "Cloud Backup Throttle Port 80"

Remove-NetQosPolicy -Name "Cloud Backup Throttle Port 443"

Remove-NetQosPolicy -Name "AOS Replication Throttle"