From VLAN Tag to Segment: Using Guest VLAN Tagging in NSX

Guest VLAN Tagging alone… not great with NSX Mapping VLAN Tags to NSX Segments Step 1 – Attach the VM to a segment Step 2 – Convert the VM’s port into a parent port Step 3 – Create child ports for each VLAN Notes Configuration steps VM Configuration Creation of a child port using API Step 1 – Retrieve the VM’s Port Step 2 – Convert the Port into a Parent Port Step 3 – Create a Child Port for VLAN 10 Creation of a Child Port for via UI Related Articles From VLAN Tag to Segment: Using Guest VLAN Tagging in NSX Save Costs and Scale Efficiently with vSAN Deduplication in VMware Cloud Foundation 9.0 How to Connect your VMware Private AI Services Agents to OpenWeb UI By default, a virtual machine sends traffic to its vNIC untagged. The virtual switch then receives that traffic into a single VLAN or NSX segment. This model limits a VM to connecting to at most 10 networks directly. But what if we need to connect the VM to more than 10 networks? With VLAN-backed networking, this is where Guest VLAN Tagging (GVT) comes in. When Guest VLAN Tagging is enabled on a port group, the VM itself is responsible for inserting VLAN tags (802. 1Q C-TAGs) into the frames it transmits. The virtual switch then uses the tag to direct the frame to the correct VLAN. With this approach, a single vNIC can access up to 4,094 VLAN-backed networks , dramatically increasing connectivity without adding more virtual NICs. Guest VLAN Tagging is enabled by specifying a VLAN ID range on the port group. For example, if you configure a range of 10–20, the vNIC will accept traffic tagged with VLAN IDs from 10 to 20, while dropping traffic tagged with IDs outside that range. The VM’s operating system must, of course, be configured to generate the appropriate VLAN-tagged subinterfaces. Guest VLAN Tagging can also be configured on NSX segments in a similar way, but there is an important difference: NSX segments are not identified by VLAN IDs.