Automated S-BFD discriminator distribution

It is possible to automatically map an S-BFD remote IP address with its discriminator using IGP routing protocol extensions. The required protocol extensions are introduced by RFC 7883 for IS-IS and RFC 7884 for OSPF. These extensions provide the encodings to advertise the S-BFD discriminators as opaque information within the advertised IGP link state information. BGP-LS added extensions allow the export of IS-IS and OSPF S-BFD discriminator information using encodings defined in draft-ietf-idr-bgp-ls-sbfd-extensions-01.

Two preconditions must apply before automated mapping of S-BFD discriminators is enabled:

traffic-engineering

This enables the TE-DB infrastructure to create the mapping between an IP address and an S-BFD discriminator.

Note: traffic-engineering is not supported in VPRN or for OSPFv3.

advertise-router-capability

This encodes the S-BFD discriminator in OSPF or IS-IS opaque Router Information TLVs.

The following is an example of an OSPF configuration output:

A:Router-A>config>bfd# info detail
        seamless-bfd
            reflector "aaa"
                no description
                discriminator 525002
                local-state up
                no shutdown
            exit
        exit

A:Router-A>config>router>ospf# info 
----------------------------------------------
            router-id 10.20.1.1
            traffic-engineering
            advertise-router-capability area
            area 0.0.0.0
                interface "system"
                    no shutdown
                exit
                interface "to_Router-C"
                    hello-interval 2
                    dead-interval 10
                    metric 1000
                    no shutdown
                exit
                interface "to_Router-B"
                    hello-interval 2
                    dead-interval 10
                    metric 1000
                    no shutdown
                exit
            exit
            no shutdown
----------------------------------------------
*A:Dut-A>config>router>ospf#