EVPN-VxLAN and Symmetric/Asymmetric IRB configuration in SONiC

SONiC: The Linux of Network Fabrics

Image Source: Copilot

[This is the second post in series focused on SONiC-Network Operating System and its applications in data center networking]

Summary of posts:

1. SONiC Architecture
2. EVPN-VxLAN, Asymmetric/Symmetric IRB
3. EVPN Multi-homing
4. MC-LAG, LACP Configurations
5. SONiC configurations & interfaces
6. Static Anycast gateway configurations

Overview of VxLAN

VxLAN encapsulates Ethernet frames within a Layer 4 UDP over a Layer 3 IPv4 or IPv6 packet, embedding a Virtual Network Identifier (VNI) field. VLAN IDs are mapped to VNI IDs, effectively creating a MAC-in-UDP encapsulation.

VxLAN Packet Format

VxLAN uses a VNI (VxLAN Network Identifier) to define broadcast domains and introduces its own packet format. The VTEP (VxLAN Tunnel Endpoint) maps VLANs to VNIs, functioning as a gateway within the VxLAN network. It is responsible for encapsulation and decapsulation, specifying the VNI for each VLAN, encapsulating packets into the…