A Virtual Local Area Network (VLAN) is a logically defined network that partitions an existing network. The use of VLANs is a straightforward means to segment and isolate these various types of traffic without the added complexity and expense of multiple physical networks and additional network adapters.
VLAN tagging is how a logical VLAN is mapped and presented for use to the Hyper-V host and a VM’s NIC traffic. The VLAN is assigned as a number corresponding to the logical network number on the physical switch port. If a VLAN tag is assigned as a default on a switch port, a VLAN tag in Hyper-V is not necessary, as the network traffic will automatically be assigned the VLAN tag after the communication leaves the Hyper-V host.
To set a VLAN on a NIC, use the PowerShell cmdlet Set-NetAdapter. An example setting the VLAN to 52 is as follows:
Set-NetAdapter -Name "Ethernet 1" -VlanID 52
If a network traffic source is exceptionally demanding, such as high I/O workloads, consider extending this separation to a new physical network – not just a logical one on the same network. Use additional physical NICs and physical switch ports or switches dedicated to a traffic source, such as iSCSI traffic for CSVs, to fully maximize the available throughput and minimize congestion with other traffic types and sources.