Users Guide

transmits on the virtual-network bridge domain. The VLAN ID regenerates using the VLAN ID associated with the virtual-network egress
interface on the VTEP and is included in the packet header.
Configure untagged access ports
Add untagged access ports to the VXLAN overlay network using either a switch-scoped VLAN or port-scoped VLAN. Only one method is
supported.
• To use a switch-scoped VLAN to add untagged member ports to a virtual network:
1. Assign a VLAN to a virtual network in VLAN Interface mode.
interface vlan vlan-id
virtual-network vn-id
exit
2. Configure port interfaces as access members of the VLAN in Interface mode.
interface ethernet node/slot/port[:subport]
switchport access vlan vlan-id
exit
Packets received on the untagged ports transmit over the virtual network.
• To use a port-scoped VLAN to add untagged member ports to a virtual network:
1. Create a reserved VLAN ID to assign untagged traffic on member interfaces to a virtual network in CONFIGURATION mode. The
VLAN ID is used internally for all untagged member interfaces on the switch that belong to virtual networks.
virtual-network untagged-vlan untagged-vlan-id
2. Configure port interfaces as trunk members and remove the access VLAN in Interface mode.
interface ethernet node/slot/port[:subport]
switchport mode trunk
no switchport access vlan
exit
3. Assign the trunk interfaces as untagged members of the virtual network in VIRTUAL-NETWORK mode. You cannot use the
reserved VLAN ID for a legacy VLAN or for tagged traffic on member interfaces of virtual networks.
virtual-network vn-id
member-interface ethernet node/slot/port[:subport] untagged
exit
If at least one untagged member interface is assigned to a virtual network, you cannot delete the reserved untagged VLAN ID. If you
reconfigure the reserved untagged VLAN ID, you must either reconfigure all untagged member interfaces in the virtual networks to use
the new ID or reload the switch.
Enable overlay routing between virtual networks
The previous sections describe how a VTEP switches traffic between hosts in the same L2 tenant segment on a virtual network, and
transports traffic over an IP underlay fabric. This section describes how a VTEP enables hosts in different L2 segments belonging to the
same tenant VRF to communicate with each other.
NOTE:
On the S4248-ON switch, IPv6 overlay routing between virtual networks is not supported with static VXLAN.
IPv6 overlay routing is, however, supported with BGP EVPN.
Each tenant is assigned a VRF and each virtual-network interface is assigned an IP subnet in the tenant VRF. The VTEP acts as the L3
gateway that routes traffic from one tenant subnet to another in the overlay before encapsulating it in the VXLAN header and
transporting it over the IP underlay fabric.
To enable host traffic routing between virtual networks, configure an interface for each virtual network and associate it to a tenant VRF.
Assign a unique IP address in the IP subnet range associated with the virtual network to each virtual-network interface on each VTEP.
To enable efficient traffic forwarding on a VTEP, OS10 supports distributed gateway routing. A distributed gateway means that multiple
VTEPs act as the gateway router for a tenant subnet. The VTEP nearest to a host acts as its gateway router. To support seamless
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VXLAN