White Papers

Table Of Contents
When you ping for 10.1.2.1 (Vlan 20s IP on R2) from R1, the packet would get to P1 on VTEP 1 with Vlan 10, and try to get
routed out of P2 on Vlan 20.
VTEP 1 sends an ARP request for 10.1.2.1 out of P2. This gets VXLAN encapsulated at P2, and gets sent out of P3.
VXLAN encapsulated ARP request lands on VTEP 2 which is decapsulated and sent out of P5 and P6.
Packets looped back to P5 will not be forwarded again to either to P4 or P6 because of the added ACL rule 4.4.3.
R2 sends an ARP response that gets VXLAN encapsulated at VTEP 2, and reaches VTEP 1 on P4 with a VXLAN
encapsulation.
At this point, wed de-capsulate at P3, the native ARP response gets looped back via P2 , and the ARP gets resolved on P2.
Once this is complete, the existing routing and VXLAN encapsulation mechanism facilitates routing over VXLAN tunnels
between R1 and R2.
Restrictions
In case the topology has a spanning tree configuration, Please enable the no spanning-tree CLI in both, the vxlan and non
vxlan loopback port-channel.
The topology to achieve RIOT with a physical loopback is inherently susceptible to Layer 2 loops. To prevent these loops from
disrupting the network, the following egress masks need to be applied:
Any frame ingressing on a VXLAN access port is not allowed to egress out of a VXLAN loopback port.
Any frame ingressing on a VXLAN loopback port is not allowed to egress out of a VXLAN access port.
Any frame ingressing on a Non-VXLAN loopback port is not allowed to egress out of a VXLAN access port.
Any frame ingressing on a Non-VXLAN loopback port is not allowed to egress out of a VXLAN loopback port.
Routing protocols and other control protocols are not supported over VXLAN tunnel (with the exception of VRRP).
Admin VRRP is not supported over VXLAN tunnel.
While 4000 VLANS or VNIDs are supported in a Layer 2 context; for VXLAN RIOT, the number of VLANS or VNIDs supported is
limited to 1000.
Configuring VXLAN RIOT
Physical Loopback
1022
Virtual Extensible LAN (VXLAN)