Multi-protocol service chaining among devices of interconnected topology

Virtual network controllers are described that automatically generate policies and configuration data for routing traffic through physical network function (PNF) service chains in a multi-tenant data center. An example network controller includes a memory and processing circuitry configured to: automatically generate, for one or more integrated routing and bridging (IRB) units of corresponding virtual network forwarding tables of a switch of a switch fabric of a data center network, configuration information that, when deployed, causes the IRB units to direct data traffic conforming to multiple communication protocols and flowing over a plurality of virtual networks between a first set of server devices and a second set of server devices positioned outside of the switch fabric (i) toward a service device logically positioned outside of the switch fabric and coupled to the switch, and (ii) back from the service device into the switch fabric via the switch.