Configuring the Overlay: VTEP Interconnections and VNIs

VTEPs can be configured as individual vRouter interfaces. However, as discussed in the About VTEP High Availability section, VTEPs are more commonly configured on switch pairs running VRRP to support redundant logical VIPs for VXLAN termination.

In this latter case, the first step is to create a VIP instead of a regular interface.

Both cases are exemplified below (a. and b.) in the list of steps required to set up the overlay:

  1. First configure the underlay’s vRouter interfaces, with the proper MTU:

    1. Create a vRouter and add a vRouter interface for each VTEP:

CLI (network-admin@switch) > vrouter-create name <vr-name> vnet <vnet-name> router-type hardware hw-vrrp-id <id>

CLI (network-admin@switch) > vrouter-interface-add vrouter-name <vr-name> ip <network/netmask> vlan <y> mtu <mtu>

    1. For VTEP HA instead add a vRouter interface using VRRP:

CLI (network-admin@switch) > vrouter-interface-add vrouter-name <vr-name> ip <network/netmask> vlan <y> vrrp-id <id> vrrp-primary <ethz.y> mtu <mtu>

<mtu> can be set for example to 1580 bytes (or more).

  1. Once the VTEPs are created, configure the VTEP connections (also referred to as ‘tunnels’) from sources to destinations. On non-redundant switches, the tunnel is created with scope local whereas on redundant switches the tunnel is created with scope cluster:

CLI (network-admin@switch) > tunnel-create name <tunnel-name> local-ip <ip1> remote-ip <ip2> scope local vrouter-name <vr-name>


CLI (network-admin@switch) > tunnel-create name <tunnel-name> local-ip <vip1> remote-ip <vip2> scope cluster vrouter-name <vr-name> peer-vrouter-name <peer-vr-name>

  1. Then create the mappings between VNIs and VLANs on the respective switches:

CLI (network-admin@switch) > vlan-create scope <scope> id <vlan-id> vxlan <vnid>

Note: A VLAN can be associated to a VNI when created on a VTEP HA pair with the vlan-create scope cluster id <vlan-id> vxlan <vnid> command. Also, the mappings can be set up also with the vlan-modify id <vlan-id> vxlan <vnid> command after VLAN creation.

Then, to add ports to a VLAN created with vlan-create command, use the vlan-port-add command, for example:

CLI (network-admin@switch) > vlan-port-add vlan-id <vlan-id> ports <port numbers>

To delete a VLAN with its mapping, use the vlan-delete command. 

Lastly, to display the information about a VLAN, for example to verify a VNI mapping and the list of ports added to it, use the vlan-show command:

CLI (network-admin@switch) > vlan-show id 70 format id, type, vxlan, scope, description, ports, untagged-ports layout vertical

id:        70

type:        public

vxlan:        70000

scope:        cluster

description:        vlan-70

ports:        0-2, 5-48, 50-52, 54-56, 63-70,272-273, 275-276, 278-280, 397        

untagged-ports: none                

  1. Add the required VNI mappings to the VXLAN connections:

CLI (network-admin@switch) > tunnel-vxlan-add name <tunnel-name> vxlan <vnid>

  1. For monitoring VXLAN specific states and statistics, use the following commands:


Displays the VXLAN ID associated with the VLAN ID.


Displays the configured tunnel and the state.


Displays the port used for BUM traffic re-circulation.


Displays statistics for each port.


Displays statistics for each tunnel.


Displays statistics for each VXLAN ID.

Note: The above configuration model is called ‘manual VXLAN tunnel creation’ and is preferred for example when the user needs to have maximum control and granularity of configuration. On the other hand, when more automation is needed, an alternate configuration model is available and is described below in the Configuring VTEP Objects with Automatic Fabric Connections section.