How to Configure Hyper-V Virtual Switch Minimum Bandwidth Modes in Windows 11 Using PowerShell

In virtualized enterprise environments running on Windows 11, multiple virtual machines frequently share a single physical network uplink. Under heavy network traffic, non-critical background workloads—such as bulk file transfers or backup jobs—can saturate the physical network adapter, causing bandwidth starvation and packet drops for mission-critical services like domain controllers, database clusters, or live video feeds.

To guarantee network bandwidth fairness, Hyper-V supports Quality of Service (QoS) bandwidth management directly on virtual switches. When provisioning a virtual switch, administrators can configure the MinimumBandwidthMode. This setting determines how the hypervisor enforces minimum bandwidth reservations for virtual machine adapters and the host management operating system. Using PowerShell, administrators can inspect, provision, and configure bandwidth reservation modes.

Understanding Hyper-V MinimumBandwidthMode Options

Hyper-V supports three distinct modes for managing minimum bandwidth reservations on external virtual switches:

• None: Disables minimum bandwidth reservations on the virtual switch. Virtual machines compete for bandwidth on a best-effort basis without guaranteed reservation floors.
• Weight: Proportional bandwidth allocation. Network adapters are assigned relative integer weights between 1 and 100. Bandwidth is distributed proportionally based on relative weight values when the physical uplink is congested.
• Absolute: Fixed-rate bandwidth reservation. Bandwidth reservations are assigned as explicit bit rates (such as 500MB or 1GB) in bits per second. The sum of all reservations cannot exceed the total physical link capacity.

Note: The MinimumBandwidthMode property must be defined during the creation of the virtual switch using New-VMSwitch; it cannot be altered on an existing switch without recreating the virtual switch.

Checking Host Physical Adapter Capabilities

Before deploying QoS bandwidth modes on a virtual switch, inspect the host physical network adapters to confirm link speed and hardware QoS offload support:

Get-NetAdapter | Select-Object Name, InterfaceDescription, LinkSpeed, Status

Ensure that the target physical adapter is active and that your intended bandwidth reservations do not exceed physical capabilities.

Inspecting Existing Virtual Switches and Bandwidth Modes

Open an elevated PowerShell prompt on Windows 11 and query the bandwidth reservation configuration across all existing virtual switches:

Get-VMSwitch | Select-Object Name, SwitchType, MinimumBandwidthMode, BandwidthReservationMode

Default virtual switches created via Hyper-V Manager typically report None or Default under MinimumBandwidthMode.

Creating a Virtual Switch with Proportional Weight Allocation

Weight-based allocation is the most common model for shared enterprise environments because it scales dynamically across differing physical link speeds (e.g. 1 Gbps, 10 Gbps, or teamed adapters). Create an external virtual switch with -MinimumBandwidthMode Weight:

New-VMSwitch -Name "QoS-VirtualSwitch" -NetAdapterName "Ethernet" -MinimumBandwidthMode Weight -AllowManagementOS $true

Confirm the new switch properties:

Get-VMSwitch -Name "QoS-VirtualSwitch" | Select-Object Name, MinimumBandwidthMode

The command confirms that MinimumBandwidthMode is set to Weight.

Assigning Bandwidth Weights to Virtual Machines

Once the virtual switch is operating in Weight mode, assign minimum bandwidth weights to connected virtual machines using Set-VMNetworkAdapter. For example, to guarantee a high priority to a production database server while assigning baseline weight to a test server:

# Assign high priority weight (50) to production database
Set-VMNetworkAdapter -VMName "DB-Server" -MinimumBandwidthWeight 50

# Assign standard priority weight (20) to web frontend
Set-VMNetworkAdapter -VMName "Web-Server" -MinimumBandwidthWeight 20

# Assign baseline weight (10) to development test machine
Set-VMNetworkAdapter -VMName "Dev-Test" -MinimumBandwidthWeight 10

When the physical adapter is saturated, the hypervisor guarantees that “DB-Server” receives at least 50/80 (62.5%) of available bandwidth, “Web-Server” receives 20/80 (25%), and “Dev-Test” receives 10/80 (12.5%). When the network is idle, all virtual machines can burst to full link speed.

Reserving Bandwidth for the Host Management OS

When sharing a physical network adapter between virtual machines and the Windows 11 host management operating system (-AllowManagementOS $true), ensure that host remote desktop (RDP) and management traffic cannot be starved by guest workloads. Assign a minimum weight to the host virtual adapter:

Set-VMNetworkAdapter -ManagementOS -MinimumBandwidthWeight 20

Verify that all virtual adapters on the switch have assigned weights:

Get-VMNetworkAdapter -All | Select-Object VMName, Name, MinimumBandwidthWeight, MaximumBandwidth

Creating a Virtual Switch with Absolute Bandwidth Allocation

In dedicated environments requiring guaranteed bit rates (e.g., reserving precisely 2 Gbps on a 10 Gbps adapter for storage replication), create the switch with -MinimumBandwidthMode Absolute:

New-VMSwitch -Name "Absolute-VirtualSwitch" -NetAdapterName "Ethernet 2" -MinimumBandwidthMode Absolute -AllowManagementOS $true

Assign explicit bandwidth reservations using -MinimumBandwidthAbsolute:

# Reserve 500 Mbps for management OS
Set-VMNetworkAdapter -ManagementOS -MinimumBandwidthAbsolute 500MB

# Reserve 2 Gbps for high-throughput guest VM
Set-VMNetworkAdapter -VMName "StorageReplica-VM" -MinimumBandwidthAbsolute 2GB

Monitoring and Troubleshooting Bandwidth Enforcement

To verify that Hyper-V bandwidth policies are actively enforced without packet drop anomalies, inspect the network adapter QoS counters:

Get-NetAdapterQos -Name "Ethernet"

By properly provisioning MinimumBandwidthMode on Hyper-V virtual switches through PowerShell, systems administrators establish predictable network performance and prevent noisy neighbour issues across Windows 11 virtualisation hosts.