Mastering Service Function Chaining in OpenStack: A Deep Dive into networking‑sfc
This article explains Service Function Chaining (SFC), its role in SDN, the architecture defined by RFC 7665 and RFC 8300, and how OpenStack’s networking‑sfc project implements SFC through concepts such as port pairs, port pair groups, port chains, service graphs, and various forwarding modes.
4. Application Example
An example service graph built with networking‑sfc uses four port chains, each representing a single service function. Virtual machines act as source, destination, and service functions across two physical hosts connected via a VXLAN tunnel. Due to an OVS bug with NSH, MPLS is used for SFC encapsulation.
Flow tables are modified so that at branching or merging points, the previous chain's egress port label is stored in reg0, then resubmitted to match on reg0 and the flow classifier, directing traffic to the appropriate group table.
360 Zhihui Cloud Developer
360 Zhihui Cloud is an enterprise open service platform that aims to "aggregate data value and empower an intelligent future," leveraging 360's extensive product and technology resources to deliver platform services to customers.
How this landed with the community
Was this worth your time?
0 Comments
Thoughtful readers leave field notes, pushback, and hard-won operational detail here.