VXLAN Inter-Subnet Routing with Symmetric IRB
VXLAN supports inter-subnet routing using Integrated Routing and Bridging (IRB). In symmetric IRB, both ingress and egress VTEPs perform Layer 3 forwarding to ensure efficient packet forwarding across subnets.
# A. Both the ingress VTEP and egress VTEP forward packets based on the Layer 3 forwarding table.
* In symmetric IRB, both ingress and egress VTEPs perform Layer 3 lookup and forwarding.
* The ingress routes packets before encapsulating them in VXLAN, and the egress performs another Layer 3 lookup to determine final delivery.
# D. When VTEPs forward inter-subnet user communication packets, the VNI carried in the VXLAN header is the L3VNI.
* L3VNI (Layer 3 VXLAN Network Identifier) is used for inter-subnet routing between VXLAN segments.