Introducing data center fabric, the next-generation Facebook data center network

This post introduces the 'data center fabric' as a next-generation network architecture for Meta's data centers, moving away from traditional cluster-based designs. It details a disaggregated approach using 'pods' as uniform network units, connected by spine switches across independent planes. The fabric utilizes standard BGP4 for routing with centralized override, is all layer3 and dual-stack (IPv4/IPv6), and heavily employs ECMP with flow-based hashing. It allows for gradual scalability from 4:1 to 1:1 fabric oversubscription by adding spine switches. The physical infrastructure is optimized for rapid deployment with shorter cabling lengths.