NSX – VXLAN Configuration

Now the hosts are prepared it’s time to build the logical network and the control plane for NSX between the cluster resources and the controllers. Sounds complicated! To accomplish this we need to  configuring VXLAN for the corresponding ESXi clusters, which will create VTEP interfaces on the hosts.

Start by navigating to the Web Client > Networking & Security > Installation > Host Preparation. Now that the cluster has been configured for NSX and all hosts show a status of Ready, the option to configure VXLAN becomes available. Click on the Configure link under the VXLAN column for the vSphere cluster.


A wizard will open asking for the VXLAN networking configuration details. This will create a new VMkernel port on each host in the cluster as the VXLAN Tunnel Endpoint (VTEP).

  • Switch – The virtual switch used for attaching the new VTEP VMkernel port.
  • VLAN – The VLAN ID to use.
  • MTU – The Maximum Transmission Unit, or the size of the payload (in bytes) that will be used within the frame. The recommended value is 1600, which allows for the overhead incurred by VXLAN encapsulation. Worth making sure the virtual switches, portgroups and physical switches are all ok with this increased MTU size. In my case I have already configured VSAN and iSCSI so jumbo frames have been enabled.
  • VMKNic IP Addressing – Select IP Pool over a DHCP Client.
  • VMKNic Teaming Policy – The method used for bonding the vmnics (physical NICs) for use with the VTEP port group.
  • VTEP Value – The number of VTEPs per host is determined by the previous selection.


If you opt to create an IP Pool (like I have), you will get a new pop up requesting the following information:

  • Name – Name of the IP Pool (something descriptive like VXLAN_VTEPs)
  • Gateway – The gateway address to leave the subnet.
  • Prefix Length – The subnet mask in CIDR notation.
  • Primary DNS – The primary IP address used for DNS lookups.
  • Secondary DNS – The secondary IP address used for DNS lookups.
  • DNS Suffix – The suffix to use when looking up host names.
  • Static IP Pool – The range of IP addresses that you are granting to NSX for VTEP VMkernel interfaces.

This can also be done by browsing to Web Client > Networking & SecurityNSX Managers > NSX Manager > Grouping Objects > IP Pools

It will take a few minutes or so for the configuration to complete. You’ll see the VXLAN status for the cluster change to Configured. Click on the Logical Network Preparation tab and make sure the VXLAN Transport sub-tab is selected. Expand the cluster to see each host’s new VMkernel interface and assigned IP address from the pool.


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