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:
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#