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Bridge and Virtual Routing and Fording (VRF)

In RARE/freeRtr you have 2 major constructs:

  • bridge for L2
  • VRF for L3

Bridge (Wikipedia)

A network bridge is a computer networking device that creates a single, aggregate network from multiple communication networks or network segments. This function is called network bridging.

In RARE/freeRtr, bridge in RARE/FreeRtr can be configured with the following command:

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FREERTR(cfg)#bridge ?                                                                                                          
  <num> - number of bridge group

FREERTR(cfg)#bridge 1 ?                                                                                                        
  <cr>

Warning

Do not forget to export bridge(s) into server p4lang so that the dataplane will take it into account into its hardware forwarding operation

Virtual routing forwarding (Wikipedia)

Virtual Routing Forwarding (VRF) is a technology included in IP (Internet Protocol) network routers that allows users to configure multiple routing table instances to simultaneously co-exist within the same router. VRFs are used for network isolation/virtualization at Layer 3 of the OSI model, the overlapping IP addresses can be used without conflicting because the multiple routing instances are independent and can select different outgoing interfaces. A VRF requires a forwarding table that designates the next-hop for each data packet, a list of devices that may be called upon to forward the packet and a set of rules and routing protocols that govern how the packets will be forwarded. These tables prevent traffic from being forwarded outside a specific VRF path and also keep out traffic that should remain outside the VRF path. Thus, the packets will be forwarded only between interfaces that belongs to the same VRF.

In RARE/freeRtr, vrf in RARE/FreeRtr can be configured with the following command:

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AMS0001(cfg)#vrf definition MY_?                                                                                               
type <name> to name of vrf

AMS0001(cfg)#vrf definition MY_VRF ?                                                                                           
  <cr>

AMS0001(cfg)#exit

Warning

Do not forget to export vrf(s) into server p4lang so that the dataplane will take it into account into its hardware forwarding operation