🧭 Complete Bring-Up Flow — Whitebox Switch (Example: UfiSpace S9600-32X with SONiC) ┌─────────────────────────────────────┐ │ BMC (AST2500 / AST2600) │ │ • IPMI / Web console / SOL │ │ • Power control, sensors, fans │ │ • Out - of - band port (eth0) │ └─────────────────────────────────────┘ │ ▼ ┌────────────────────────────────────────────────────────────┐ │ x86 / ARM Host CPU │ │ ( where ONIE and later SONiC run) │ └────────────────────────────────────────────────────────────┘ │ (boot process) ▼ ⚙️ Stage 1 – Power-On & BMC Initialization BMC powers up first. It’s an independent microcontroller (running its own Li...

  🧭 Switch Architecture – Control vs Data Plane ┌───────────────────────────────────────────────────────────┐ │ User Layer │ │ ┌─────────────────────────────────────────────────────┐ │ │ │ CLI / REST / gNMI / SNMP / Ansible / gRPC Clients │ │ │ └─────────────────────────────────────────────────────┘ │ └───────────────────────────────────────────────────────────┘ │ ▼ ┌───────────────────────────────────────────────────────────┐ │ Network OS (NOS) │ │ ┌─────────────────────────────────────────────────────┐ │ │ │ Routing, BGP, OSPF, EVPN, MPLS, QoS, ACL modules │ │ │ ├─────────────────────────────────────────────────────┤ │ │ │ Hardware Abstraction Layer (HAL / SAI) │ │ │ │ (translates generic NOS APIs → ASIC-specific SDK) │ │ │ └─────────────────────────────────────────────────────┘ │ └───────────────────────────...

  🧩 1️⃣ Physical View — What’s inside a Whitebox Switch Inside your UfiSpace S9600-32X (or similar platforms), the architecture looks like this: + ------------------------------------------------------+ | Switch System - on -Chip (Broadcom Q2C) | | | | + -----------------+ +------------------+ | | | Packet ASIC |< -----> | CPU (x86/ARM) | | | + -----------------+ +------------------+ | | | | | | | | | 32 x100G ports Mgmt (ma1) | | | | [ BMC Chip (IPMI) ] — out - of -band mgmt | + ------------------------------------------------------+ So: ASIC handles all the packet forwarding , port control, VLAN, ACL, routing, etc. CPU runs Linux/NOS (like RtBrick, SONiC, or ONL) and programs the ASIC via software APIs. BMC...

 

 

  Here is the step-by-step MAC address learning flow in EVPN-VXLAN using a Route Type-2 advertisement. This process leverages a control-plane approach to exchange MAC reachability information, which greatly improves scalability compared to the traditional data-plane flood-and-learn method of classic VXLAN.   Topology overview We will use a simple topology with two hosts, Host A and Host B, residing in the same Layer 2 segment (VLAN 10, VNI 10010) but connected to different leaf switches, Leaf 1 and Leaf 2, respectively.   Key tables involved: Layer 2 MAC Table (Switching table):  This is the familiar table that maps a MAC address to a port. In EVPN, entries can point to either a local access port or the VXLAN Network Virtualization Edge (NVE) interface. L2RIB (Layer 2 Routing Information Base):  A specialized table on the VTEP that stores Layer 2 routing and reachability information. It acts as an intermediate database, storing locally learned MACs and BGP-adver...